1995 Impala SS - Oil Issues

Hi All,

I've recently noticed that my Impala has been having oil issues.

Only two weeks after the last oil change, the "Low Oil Level" light came on. I checked the dipstick and there was nothing on it - except after reving of course.

I did not see any tell-tale leak spots anywhere.

However, I do notice an oil-burning smell every time I gun it.

The headgaskets were redone about 3000 miles ago so I cant see the valves being an issue.

I guess it is important ot mention that the oil level seemed fine before the oil change.

Any ideas?

Hi All,

I've recently noticed that my Impala has been having oil issues.

Only two weeks after the last oil change, the "Low Oil Level" light came on. I checked the dipstick and there was nothing on it - except after reving of course.

I did not see any tell-tale leak spots anywhere.

However, I do notice an oil-burning smell every time I gun it.

The headgaskets were redone about 3000 miles ago so I cant see the valves being an issue.

I guess it is important ot mention that the oil level seemed fine before the oil change.

Any ideas?

did I ever tell you about my friend ED....
prior to driving to atlantic city he got an oil change...when in new york city, the engine light came on....when he checked the oil it was down 3.5qts.....

well it was never filled properly ,,and he foolishly did not check it before driving from the service center...

ED now checks the oil, when it is changed..

I'm glad 'ED' learned his lesson. :grinno: Strange that 'ED's car's oil light came in on new York City even though he was headed to Atlantic City.

I have started to do the same.

Ironically, after the oil change, I, too, took a long drive, like 'ED'.

No oil lights came on during that trip.

j cAT, you correctly assumed that the oil was changed by a 'service center'.

However, the oil change was done by a friend and his coworkers at a local Pep Boys, i.e. they wouldn't pull something like that.

But that is not to say it couldn't happen...

Right now, my main concern is the oil-burning smell when accelerating semi-heavy.

Any ideas?

I'm glad 'ED' learned his lesson. :grinno: Strange that 'ED's car's oil light came in on new York City even though he was headed to Atlantic City.

I have started to do the same.

Ironically, after the oil change, I, too, took a long drive, like 'ED'.

No oil lights came on during that trip.

j cAT, you correctly assumed that the oil was changed by a 'service center'.

However, the oil change was done by a friend and his coworkers at a local Pep Boys, i.e. they wouldn't pull something like that.

But that is not to say it couldn't happen...

Right now, my main concern is the oil-burning smell when accelerating semi-heavy.

Any ideas?


back in the 1980's the oil light would come on only when you basicly had very little oil....today most vehicles have a oil level sensor...

his check engine light came on,,,it was because the oil was not suffecient to properly cool/ lubricate the engine...

in your case I would say that this was an accident that they did not place the correct amount of oil in the crankcase.....this is quite common...not that this was done on purpose...to save the service center some profit..

how many miles on vehicle ? have you checked/replaced the PCV/hoses lately...this vehicle has some crankcase vent hoses that at this age need replacing...mine did last year 1996 impala...especially at the PCV 90deg hose bend...

with the crankcase vent inop.. this could be your smoke out the exhaust problem..

Yeah, I'd have to agree there is a possibility that they did not put in enough oil. But I don't see saving money/profit as the cause simply because This was a personal friend who took care of it.

My car is a '95. I recently purchased it from a mechanic shop about 3000 miles ago. The headgasket went out after only 25 miles of driving due to a clogged radiator (so I was told).

The car's engine was stroked to a 383 about 15-20,000 miles ago by the shop that sold it to me. The transmission and the rearend were also beefed up later on down the line. The car itself has 136,600 miles.

I have not checked nor replaced the PCV and hoses but I will look at them first chance I get. I did notice that the the valve cover have two piston-looking caps on one cover and just a billet one on another. I don't have that on my '96 LT1 Z28. When I went to add the oil, I didn't see the regulay oil pouring spout so I just removed the billet one and poured it in from there.

By the way, the shop replaced the headgaskets when they went out. To cool down the coor even more, they took out the thermostat and wired the fans directly to the battery. The car was running super cold like you will not believe. But it was also shifting hard (which it still does, supposedly due to the performancy nature of the transmission, but not as hard). I placed in a stock temperature thermostat (195 degrees) and it now warms up some. I wonder if that may have something to do with it the oil burning.

Thanks for the tips and ideas, j cAT. I'm gonna check on what you mentioned and see what I find. I'll try to have someone follow me to see if they observe any smoke.

Yeah, I'd have to agree there is a possibility that they did not put in enough oil. But I don't see saving money/profit as the cause simply because This was a personal friend who took care of it.

My car is a '95. I recently purchased it from a mechanic shop about 3000 miles ago. The headgasket went out after only 25 miles of driving due to a clogged radiator (so I was told).

The car's engine was stroked to a 383 about 15-20,000 miles ago by the shop that sold it to me. The transmission and the rearend were also beefed up later on down the line. The car itself has 136,600 miles.

I have not checked nor replaced the PCV and hoses but I will look at them first chance I get. I did notice that the the valve cover have two piston-looking caps on one cover and just a billet one on another. I don't have that on my '96 LT1 Z28. When I went to add the oil, I didn't see the regulay oil pouring spout so I just removed the billet one and poured it in from there.

By the way, the shop replaced the headgaskets when they went out. To cool down the coor even more, they took out the thermostat and wired the fans directly to the battery. The car was running super cold like you will not believe. But it was also shifting hard (which it still does, supposedly due to the performancy nature of the transmission, but not as hard). I placed in a stock temperature thermostat (195 degrees) and it now warms up some. I wonder if that may have something to do with it the oil burning.

Thanks for the tips and ideas, j cAT. I'm gonna check on what you mentioned and see what I find. I'll try to have someone follow me to see if they observe any smoke.


I am only very familiar with the stock LT1 engine,,the engine you have has some differences...which I don't know much about..

the fans should never be on all the time,,,this was not designed to run all the time, and will burn out..

the pluged radiator was because they/previous owner used the wrong antifreeze or, mixed dexcool with silicone antifreeze...

my coolant systems never had these corroded, pluged problems as many have had,,,the dexcool with distilled water is how this is prevented,

also by removal of the knock sensors you can drain the complete coolant system,,about 4 gallons total with the heater core which needs to be back flushed because it has a habit of getting pluged with debis//very common..

since you just purchased this vehicle, hopefully you will not have any more expensive repairs...these vehicles will last a long time with few problems,,, but care must be taken to have the proper maintanence done at the correct time..

On the thermostat,,, my engine uses a 180deg F GM #12555290 a/c #131-100

Well it is a stock LT1 block stroked out to a 383 with forged internals and Edelbrock heads.

Yeah, I agree with you about the fans running all the time myself. I'm gonna go ahead and install the manual switch instead. Any experience with that?

About the clogged radiator, I think it may have something to do with the fact that the car had been sitting around for quite a few months. Could that clog up the radiator, or some other component of the cooling system? I'm not a big fan of DexCool and the shop actually put in the green coolant after the headgasket was replaced.

I did some research on the car itself before buying it was impressed with its looks, power, room and reliability. I figured the 383 pushing over 400 hp was a nice bonus. Hopefully no problems in the future. Its been getting me around reliably so far, albeit with some crappy gas mileage.

I am going to try the thermostat you mentioned, by the way. Acording to the shop, the ECU was programmed for the 160 degree thermostat so I was suprised to find no thermostat - nothing but the top part with the rubber seal to keep the water outlet from leaking. I think the previous owner kinda got carried away with odifying it and didn't kno what he was doing at times.

Also, it is running Denso iridium spark plugs. Any opinions?

Thanks again j cAT...

Well it is a stock LT1 block stroked out to a 383 with forged internals and Edelbrock heads.

Yeah, I agree with you about the fans running all the time myself. I'm gonna go ahead and install the manual switch instead. Any experience with that?

About the clogged radiator, I think it may have something to do with the fact that the car had been sitting around for quite a few months. Could that clog up the radiator, or some other component of the cooling system? I'm not a big fan of DexCool and the shop actually put in the green coolant after the headgasket was replaced.

I did some research on the car itself before buying it was impressed with its looks, power, room and reliability. I figured the 383 pushing over 400 hp was a nice bonus. Hopefully no problems in the future. Its been getting me around reliably so far, albeit with some crappy gas mileage.

I am going to try the thermostat you mentioned, by the way. Acording to the shop, the ECU was programmed for the 160 degree thermostat so I was suprised to find no thermostat - nothing but the top part with the rubber seal to keep the water outlet from leaking. I think the previous owner kinda got carried away with odifying it and didn't kno what he was doing at times.

Also, it is running Denso iridium spark plugs. Any opinions?

Thanks again j cAT...

the fans should be controlled by the pcm...examples of fan control would be a/c on primary fan comes on, a/c pressures too high secondary fan comes on..vehicle speed over 45 mph fans off..engine temp over 235 deg f approx. fans on...in addition to the fans wearing out this also stesses out the alternator,,,especially when hot out..

the fan relays are located in the under hood fuse box,passenger side.. I have the diagrams for this with the repair manuals for my 96 ss..with a private message give me you email address I can send you the info to aid in correcting this..

I would think that your modified engine requires the same thermostat design as the original..using a 160 deg. with the altered engine work/pcm programing may very well be good...but you must have a thermostat so the the coolant flows properly, with this reverse flow..

because the radiator was pluged you must completely drain the coolant system...as I described...then refill with the silicone antifreeze with distilled water...I say silicone because now this is in the engine metals rubber hoses etc..and switching back to the oem dexcool might cause problems...distillled water will keep the coolant from growing sludge and metal eating solutions.
using at least 50% of antifreeze,which would be 2 gallons minimum...I use 2.5 gallons when it time to replace coolant ..1.5 gallons of distilled water..


what would the a/c plug number be for this engine ? the same as original ? the irridium plugs have a hotter spark , and It is a good design ..I have not however used them..the metal tips resist heat damage and maintain a good spark over a longer time than platium..

you are using 93 octane in this ,,,? and is the MPG about 12..?

About the fans, see the head gasket went out about 25 miles after I picked it up. But here is another issue that's been bugging me: right after I bought the car, I left it at the shop fro them to repair an A/C hose that had burned up from too much heat from the passenger-side header. Apparently, either one of the fans was disconnected when the A/C hose burned up or it went bad, but I have a feeling that fan never came on because the temperature shot up after I turned the A/C on. I pulled over and then the smoke/steam came out the engine bay. The car still drove fine, however.

So I called the shop, told them what happened, and then dropped off the car. Couple of days later, I was told the head gaskets were bad and a bad radiator was to blame. Ironically, the owner admitted the fan had been disconnected at some point since the A/C was not being used due to the damaged hose. But he didn't remember if they ever reconnected it after I bought the car. It should've been a simple check. The shop kept the car for a few days, changed the gaskets, resurfaced the heads, installed a used fan and a new radiator. And apparently removed the thermostat and used the green coolant instead of Dexcool. I kid you not, the temperature gage was always at "C" from then on. I took the car for a long drive up north while going through ridiculous stop-and-go traffic and the the temp hardly moved.

So I called the shop again and told the owner how the car was running super-cold and the transmission was shifting too hard in first and second. He said it was good the car was running so cold because they always had a hard time keeping the temperature down on this car. As for the hard shifting, his explanation was that the transmission is a step below a racing transmission, so it shifts off full-line pressure.

I wasn't buying his explanation, so I bought a 195 degree thermostat to see what would happen. When I opened the thermostat housing, I was surprised to find just the top portion of the thermostat with the rubber seal. So now I don't know if the shop did this and never told me or if it was the previous owner. Anyways, the temperature now goes about 1/3 of the way up the gauge and the shifting is slightly softer.

Please forgive my lack of knowledge on the subject but what is silicone antifreeze? Any particular brands you recommend?

You know, the AC Delco plug number is a good question. I would assume it is the same. I guess the shop stayed with the stock heat range. I know the iridiums have a more precise spark due to their fine tips and the materials last longer than platinum but had my suspicions since I heard a few guys says they would last much in an American V8. I posted the same question on this forum and one guy says that the Delco iridium is best.

Right now, I use 91 gas and average about 16 mpg in the everyday driving.

WHAT BRAND, WEIGHT ETC. OF OIL WAS USED AT THE OIL CHANGE? The answers to this question may solve the oil usage issues. Most of the "modern" API SL rated oils have a very low ZDDP content as dictated by the EPA. They also seem to be thinner in content IMO than earlier oil ratings API SJ/SM. If your engine was built with FORGED internals the engine may have been built LOOSE. Forged PISTONS expand at a diffrent rate than CAST. Being built loose coupled with a thinner oil may have contributed to the excessive oil usage. There may be other threads I am sure that address these concerns. I know ZDDP has a few.

HOPE THIS HELPS NOT HINDER

About the fans, see the head gasket went out about 25 miles after I picked it up. But here is another issue that's been bugging me: right after I bought the car, I left it at the shop fro them to repair an A/C hose that had burned up from too much heat from the passenger-side header. Apparently, either one of the fans was disconnected when the A/C hose burned up or it went bad, but I have a feeling that fan never came on because the temperature shot up after I turned the A/C on. I pulled over and then the smoke/steam came out the engine bay. The car still drove fine, however.

So I called the shop, told them what happened, and then dropped off the car. Couple of days later, I was told the head gaskets were bad and a bad radiator was to blame. Ironically, the owner admitted the fan had been disconnected at some point since the A/C was not being used due to the damaged hose. But he didn't remember if they ever reconnected it after I bought the car. It should've been a simple check. The shop kept the car for a few days, changed the gaskets, resurfaced the heads, installed a used fan and a new radiator. And apparently removed the thermostat and used the green coolant instead of Dexcool. I kid you not, the temperature gage was always at "C" from then on. I took the car for a long drive up north while going through ridiculous stop-and-go traffic and the the temp hardly moved.

So I called the shop again and told the owner how the car was running super-cold and the transmission was shifting too hard in first and second. He said it was good the car was running so cold because they always had a hard time keeping the temperature down on this car. As for the hard shifting, his explanation was that the transmission is a step below a racing transmission, so it shifts off full-line pressure.

I wasn't buying his explanation, so I bought a 195 degree thermostat to see what would happen. When I opened the thermostat housing, I was surprised to find just the top portion of the thermostat with the rubber seal. So now I don't know if the shop did this and never told me or if it was the previous owner. Anyways, the temperature now goes about 1/3 of the way up the gauge and the shifting is slightly softer.

Please forgive my lack of knowledge on the subject but what is silicone antifreeze? Any particular brands you recommend?

You know, the AC Delco plug number is a good question. I would assume it is the same. I guess the shop stayed with the stock heat range. I know the iridiums have a more precise spark due to their fine tips and the materials last longer than platinum but had my suspicions since I heard a few guys says they would last much in an American V8. I posted the same question on this forum and one guy says that the Delco iridium is best.

Right now, I use 91 gas and average about 16 mpg in the everyday driving.


the headers should be covered with insulation,,,this will reduce back pressure and remove excessive heat from the engine bay..

the oem a/c lines in the exhaust manifold area have insulation rapped around them...

they installed only the top portion of the thermostat to provide a gasket seal mounting surface...

replace the 195 thermostat with a 160/ or 180 deg. F

MPG is 16 which is pretty good and 91 octane keeps it from pre-ignition..


the fan problem is what I suspected the fan burn't out from running continuosly and then it blew out the head gasket///

silicone based anti freeze is the green stuff which is what they put in...because of this you should not go back to dexcool...

my vehicle since nov 1995 coolant guage goes up 1/3,,,

the headers should be covered with insulation,,,this will reduce back pressure and remove excessive heat from the engine bay..

I don't think the headers have any insulation on them. Something to look at...


the oem a/c lines in the exhaust manifold area have insulation rapped around them...

Right now, the AC hose by the header has some kind of aluminum shield over it.


they installed only the top portion of the thermostat to provide a gasket seal mounting surface...

Right. Thats exactly what they did. That allowed the coolant to flow nonstop from startup until turned off.


replace the 195 thermostat with a 160/ or 180 deg. F

I apologize. I did install the 180 degree thermostat, not the 192 degree, and now the temperature gauge goes up one third of the way. I am interested in trying the 160 degree thermostat to see what significant changes occur.


MPG is 16 which is pretty good and 91 octane keeps it from pre-ignition..

I was told by the shop to stick 91 or I would have knocking problems. The best mileage I've gotten so far is 24 on the highway while driving between 55 - 60 mph. By the way, I've read about this only once somewhere, but is the LT4 knock sensor a good upgrade?


the fan problem is what I suspected the fan burn't out from running continuosly and then it blew out the head gasket///

Yes. I need to get in touch with you via email to get the diagrams to fix this.

silicone based anti freeze is the green stuff which is what they put in...because of this you should not go back to dexcool...

I do not like Dexcool with a passion. This is my second LT1 that lost its headgasket.


my vehicle since nov 1995 coolant guage goes up 1/3,,,

My car is showing the same temperature reading at this time.

I'm gonna check on the PVC and hoses tonight, along with possibly swtiching to the 160 degree thermostat. Results coming soon...

WHAT BRAND, WEIGHT ETC. OF OIL WAS USED AT THE OIL CHANGE? The answers to this question may solve the oil usage issues. Most of the "modern" API SL rated oils have a very low ZDDP content as dictated by the EPA. They also seem to be thinner in content IMO than earlier oil ratings API SJ/SM. If your engine was built with FORGED internals the engine may have been built LOOSE. Forged PISTONS expand at a diffrent rate than CAST. Being built loose coupled with a thinner oil may have contributed to the excessive oil usage. There may be other threads I am sure that address these concerns. I know ZDDP has a few.

HOPE THIS HELPS NOT HINDER

Hey NovaZ27,

This definietly helps.

The oil used was Mobil 1 5w30 synthetic.

Perhaps too thin for a motor like this?

Although the shop owner said that the previous owner was running this weight with no issues.

I added regular Mobil 10w30 when the level dropped. I actually added extra in case more oil burned. I just check the oil and the level is still the same. So perhaps thickness is indeed the issue.

But still, any ideas why the burning smell when accelerating?

j cAT mentioned PVC and hoses but I haven't check them yet (because I dunno where the PCV is located :p)...

You know what? I think I know what it may possibly be. When I checked the oil level just now, I noticed the dip stick tube was moving. Possible oil could be leaking out of there and onto the headers, there by casuing the burning smell?

Appreciate the help...

Hey j cAT,

I just went to check the oil level for NovaZ27 and ended up taking a look at the headers.

The headers have no insulation. The two AC hoses in the passenger-side area, along with a wire for a temperature sensor on the same side (goes into the block) are covered in a heat shield fabric with an aluminum outer layer.

MOBIL 1 SYNTHETIC is a very good product. I have used it in my vehicles for years. My favorite weight is the 15W50 that has the red cap. My "84" Caprice has 317k + mi. on it with minimal oil usage. 15w50 is designed for performance vehicles with 1200 ppm phosphrous & 1300 ppm zinc according to the MOBIL 1 website. This weight might be the ticket for your ride. You might watch it when you switch to a 160 degree thermostat. Going cooler might trick the computer into thinking the engine is running to cool causing it to signal the injectors to run a richer mixture. Result less mpg. Do run a thermostat leaving it out circulates the coolant to fast thru the radiator resulting in less heat transfer. My uncle did this on an old FORD flathead. Those twin water pumps really circulated the coolant thru the radiator but the temp still went way high. He just about burned her up.

MOBIL 1 SYNTHETIC is a very good product. I have used it in my vehicles for years. My favorite weight is the 15W50 that has the red cap. My "84" Caprice has 317k + mi. on it with minimal oil usage. 15w50 is designed for performance vehicles with 1200 ppm phosphrous & 1300 ppm zinc according to the MOBIL 1 website. This weight might be the ticket for your ride.

Hmmm… 15w50 is a lot higher than what I would expect to use in a low-mileage engine (136kmiles on car, 35k miles on rebuilt engine). But it seems the thicker oil I added (10w30 conventional) is lasting in the car just fine right now.

Still can’t figure out what’s causing the burning smell during acceleration though… I’m going to change the oil myself this weekend and then I’ll see what happens.


You might watch it when you switch to a 160 degree thermostat. Going cooler might trick the computer into thinking the engine is running to cool causing it to signal the injectors to run a richer mixture. Result less mpg. Do run a thermostat leaving it out circulates the coolant to fast thru the radiator resulting in less heat transfer. My uncle did this on an old FORD flathead. Those twin water pumps really circulated the coolant thru the radiator but the temp still went way high. He just about burned her up.

Yes, I totally agree with you. I figured running the car too cold would make the computer dump in more fuel to warm up the engine, which obviously kills gas mileage as well.

After I installed the 180 degree thermostat, the gas mileage went up slightly but I noticed better throttle response and deeper exhaust note from the Flowmaster American Thunders.

The thing about LT1 engine is that, since they are reverse-flow cooling, meaning the heads are cooled first, and the factory head gaskets seems to be made of weak materials, some people end up trying to keep the engine as cold as possible.

Mobil 1 15w50 is considered a racing oil by Exxon/Mobil. Good stuff for a roller or flat tappet motor. It stays in the motor. In sunny California you should not have to worry about the w50 part of 15w50. I live in the Kansas City area and have never had any problems. Summer/Winter.
How long did you run the 5w30 at the low level? Could have messed with the oil rings. What forged internals do you have in the motor? What size of oilpan do you have? Stock 5qt. or aftermarket higher capacity? When the oil was changed the tech. might have just put 5qts into lets say a 6qt. oilpan. As mentioned before a bad PCV valve will suck oil on acceleration. Have someone follow you on an acceleration run to see if the telltale white/blue oil smoke is coming out of the tailpipe/s. A bad valve guide/ seal on an intake valve could be a problem also. If you had the heads redone they could be putting to much compression pressure on some even slightly worn rings. More things to think about to make your head spin:headshake

HOPE THIS HELPS

Mobil 1 15w50 is considered a racing oil by Exxon/Mobil. Good stuff for a roller or flat tappet motor. It stays in the motor. In sunny California you should not have to worry about the w50 part of 15w50. I live in the Kansas City area and have never had any problems. Summer/Winter.

Right. I remember reading the bottle for 15w50 a few years back and it said that it was a European performance formula (might say something different now). But I don’t know if it is too thick for a low-mileage performance motor being used as a daily driver (lots of stop and go traffic).


How long did you run the 5w30 at the low level? Could have messed with the oil rings.

I drove the car for roughly two weeks before the “Low Oil” light came on. So I don’t know exactly when the level started dropping. However, when the light came on, I turned off the car and didn’t drive until I added more oil a day later. I am hoping and praying that the oil rings aren’t damaged.


What forged internals do you have in the motor?

In all honesty, I don’t exactly know what parts or brands were used off the top of my head. The owner of the shop that sold me the car said the motor was built with all forged internals and mentioned a few brands in the ad itself (of which I have a copy if needed for reference).

What size of oilpan do you have? Stock 5qt. or aftermarket higher capacity? When the oil was changed the tech. might have just put 5qts into lets say a 6qt. oilpan.

That is definitely something to look into.

To my knowledge, the car is using a stock oil pan with the 5 quart oil pan. Before the oil change, I was worried about the oil capacity myself so I asked a few shops – don’t remember if I called the seller’s shop – and they all said it should be stock capacity.


As mentioned before a bad PCV valve will suck oil on acceleration. Have someone follow you on an acceleration run to see if the telltale white/blue oil smoke is coming out of the tailpipe/s. A bad valve guide/ seal on an intake valve could be a problem also.

Yea, I need to find a day where I’m home early enough to have someone follow me during the day time. I was driving around with a friend just yesterday and I pointed out the small to him. He thinks valve seals…

If you had the heads redone they could be putting to much compression pressure on some even slightly worn rings.

I have been thinking of going back to the seller's shop and informing them of the problem. Sadly, I am losing trust in these guys. They didn't take much responsibility when the headgasket went out...

More things to think about to make your head spin

:werd:

As always, thanks for the insight and tips NovaZ27... you've been very helpful bro... along with J cAT of course...

Hey All,

So, I had a few minutes on my hand this morning so I did a quick check under the good on the PVC and hoses along with the oil level.
The oil level has dropped by about a quart since I last checked it a few days ago.

I checked the PCV and hoses and it turns out there is no hose between the throttle body and the PCV. As a matter of fact, the PCV has been replaced by a larger metal PCV with the outlet tip plugged off. The outlet tip on the throttle body is plugged off as well.

On top of all that, I found streaks of oil on the valve covers where the PCV is as well as the headers, leading me to believe it’s been leaking out.

Check out the pics below.


The metal PCV:
http://i900.photobucket.com/albums/ac208/lt1silverhawk/1248195902-1.jpg


The Throttle Body:
http://i900.photobucket.com/albums/ac208/lt1silverhawk/1248195903-1.jpg

The place where oil appears to be leaking:
http://i900.photobucket.com/albums/ac208/lt1silverhawk/1248195898-1.jpg

The mickey mouse fan wires:
http://i900.photobucket.com/albums/ac208/lt1silverhawk/1248195892-1.jpg


A lonely connector, possibly for the fan:

http://i900.photobucket.com/albums/ac208/lt1silverhawk/1248195894-1.jpg (http://i900.photobucket.com/albums/ac208/lt1silverhawk/1248195894-1.jpg)

Thanks for the help!

The only experience I have had with this model engine is my mother's 94 CAPRICE LS that has the baby LT1 (4.3 V8). From what I can see from your pictures is that the PCV has been disabled. Effectively sealing the crankcase tight. This is not good. All that crankcase pressure is blowing the oil out where ever it can. Leaking onto the header gasket is an example. If it is leaking onto the gasket some of the oil is probably hitting the very hot header pipe causing the hot oil smell. The oil is burning off the pipe completely probably not leaving any trace.
The principle behind the workings of a PCV valve is to draw off crankcase vapors i.e. "blowby" by a metered vaccum draw with the metering device being the PCV valve. The pcv valve draws the vapors into the intake to be burned but the vapors being drawn in must be replaced by a fresh air source that is usually drawn from the air cleaner on carbed engines or the plenum on fuel injected engines. any one of these pieces of the puzzle being messed with can cause trouble.
Check out the flow of your PCV system. The hose routing may be on a sticker in the engine bay.

HOPE THIS HELPS

…From what I can see from your pictures is that the PCV has been disabled. Effectively sealing the crankcase tight. This is not good. All that crankcase pressure is blowing the oil out where ever it can. Leaking onto the header gasket is an example. If it is leaking onto the gasket some of the oil is probably hitting the very hot header pipe causing the hot oil smell. The oil is burning off the pipe completely probably not leaving any trace.

My thoughts exactly… The oil is leaking out when I accelerate, falling onto the header and burning off with the heat.



Check out the flow of your PCV system. The hose routing may be on a sticker in the engine bay.

I checked the Chilton’s manual for Fbodies with LT1’s (it’s all I could find on short notice) and there is a diagram for the PCV setup and the hose goes from the throttle body to the PCV at the same locations where it is plugged off on my car.

The weird part is that there didn’t seem to be any oil burning before the last oil change.

It does leave me wondering why the PCV hose would have been removed and the valve and the throttle body plugged off. I can’t see any benefits.

I’m gonna buy a vacuum hose and put it on the throttle body and the PCV today. The original hose was a molded plastic I believe but I don’t think it should make a difference if I use an off-the-shelf one from AutoZone or Napa.

The gaskets being fairly fresh might have held up to the crankcase pressure until going thru all those heat cycles weaken them to the point that the cc pressure won out. Once they started leaking well you see/smell the results. Also the V cover bolts could have loosened up a tad after all the heat cycles. IMO the PVC valve system is one true pollution device that actually does something good on a street engine. Keeps the oil cleaner longer.

The gaskets being fairly fresh might have held up to the crankcase pressure until going thru all those heat cycles weaken them to the point that the cc pressure won out. Once they started leaking well you see/smell the results. Also the V cover bolts could have loosened up a tad after all the heat cycles.

Do you recommend redoing the valve cover gasket just to play it safe?

YOUR COVERS LOOK TO BE CAST ALUMINIUM CORRECT? IF SO THEY ARE MORE RIDGID AND DO NOT DISTORT AS EASY AS THE STAMPED STOCK ONES. BEFORE REPLACING THE GASKETS YOU MIGHT JUST SNUG THEM DOWN A BIT THEN CHECK TO SEE IF THEY STILL SEEP/LEAK. FIXING THE PCV SYSTEM MIGHT RELIEVE THE CC PRESSURE ENOUGH THAT THE GASKETS MAY HOLD. TRY THESE IDEAS OUT BEFORE SPENDING THE $$$$. IF YOU DO FEEL THE NEED TO REPLACE THE GASKETS USE A QUALITY BRAND. CHECK THE V COVERS FOR WARPAGE & FLATNESS WHILE THEY ARE OFF THE ENGINE.
PAPER vs PLASTIC. CORK/RUBBER GASKETS WORK PRETTY GOOD BUT THEY DO NOT LAST AS LONG AS THE SILCON RUBBER ONES IMO. THEY TEND TO DRY OUT, BECOME BRITTLE THEN CRACK.

HOPE THIS HELPS

the pcv / crankcase vent was removed,,,possibly to reduce blowby gasses getting into the throttle body...I suspect an engine that was abused....sorry ....

the passenger side of engine is where the vent for crankcase should be into the valve cover, this then goes into the side /top of the throttlebody that was pluged in your picture...on the driverside into the intake manifold is the PCV location...then the hose from the PCV goes into the bottom of the throttle body under the air intake ,,,,hose hard to get at....


the fan wires where hacked ,,,typical mechanic electrical job...

the oil that should be used is 10-30wt....

the lack of crankcase venting will cause the gaskets to blow out as pressures in the crankcase will do this....as well as any hoses/valve cover gaskets etc...a good running engine should have a slight vacuum in the crankcase...

with your engine running and hot I bet with the oil fill removed it smokes out of the fill hole pretty good..as it is now..


most likely they screwed up the re-build or did not properly break in the engine,,

see if it is not as serious as I suspect,,,keep us informed..

YOUR COVERS LOOK TO BE CAST ALUMINIUM CORRECT? IF SO THEY ARE MORE RIDGID AND DO NOT DISTORT AS EASY AS THE STAMPED STOCK ONES. BEFORE REPLACING THE GASKETS YOU MIGHT JUST SNUG THEM DOWN A BIT THEN CHECK TO SEE IF THEY STILL SEEP/LEAK. FIXING THE PCV SYSTEM MIGHT RELIEVE THE CC PRESSURE ENOUGH THAT THE GASKETS MAY HOLD.

Yeah the valve covers appear to be cast aluminum.

I'll definitely tighten down the bolts a bit when I replace the PCV hose.

Hopefully that take care of the problem...

First off, thank you so much j cAT for the diagrams for the fans…


the pcv / crankcase vent was removed,,,possibly to reduce blowby gasses getting into the throttle body...I suspect an engine that was abused....sorry ....
…

most likely they screwed up the re-build or did not properly break in the engine,,

Sadly, I must agree. I don’t think the guys working at the shop that built and sold me the car knew what they were doing.

I have half a mind to go to the shop and ask why they did what they did.

But I have a feeling I’ll simply get more made-up answers like I got about the 'necessity to the run the car super-cold'. :banghead: :angryfire



the oil that should be used is 10-30wt....

Yeah, that’s the oil I put in the car when the “Low Oil” light came on. It has not burned up as fast the 5w30 synthetic.

I am considering an oil change soon with a can of Restore...



the fan wires where hacked ,,,typical mechanic electrical job...
No argument there…:werd:


see if it is not as serious as I suspect,,,keep us informed..

I most definitely will. I’m gonna be out of town for the weekend but I’ll do get to it as soon as I can and let you know what happens…

These days when one takes their BABY to a shop for repair it is like going to a CASINO disguised as a repair shop. Most shops are straight up people. However there are some shops that employ either KING KONG or MICKEY MOUSE as mechanics. Like any store you go into BUYER BEWARE. Check the shop out before hand. Most dealerships want your return business so they will not mess up to often. They do not want a bad reputation for the public as well as the Vehicle Company they represent to see. A private shop should hold themselves to the same standards. If you take your BABY to any shop get everything in writing. A verbal agreement is legally null and void if a problem arises. Another small thing that nags me about having the BABY in the shop is having to wait in the WAITING ROOM reading year old magazines and drinking coffee about the same age as the magazine all because of the little sign that states DUE TO INSURANCE REASONS YOU ARE NOT PERMITTED INTO OUR SHOP.
ENOUGH about the AUTO SHOP. I hope that fixing the PCV system cures what ails your BABY. Was the smell mostly from the engine compartment? If the tail pipe burns clean you are probably all right. Keep us informed. The more we learn the more there is to learn.

MY 2 CENTS

These days when one takes their BABY to a shop for repair it is like going to a CASINO disguised as a repair shop. Most shops are straight up people. However there are some shops that employ either KING KONG or MICKEY MOUSE as mechanics. Like any store you go into BUYER BEWARE. Check the shop out before hand. Most dealerships want your return business so they will not mess up to often. They do not want a bad reputation for the public as well as the Vehicle Company they represent to see. A private shop should hold themselves to the same standards. If you take your BABY to any shop get everything in writing. A verbal agreement is legally null and void if a problem arises. Another small thing that nags me about having the BABY in the shop is having to wait in the WAITING ROOM reading year old magazines and drinking coffee about the same age as the magazine all because of the little sign that states DUE TO INSURANCE REASONS YOU ARE NOT PERMITTED INTO OUR SHOP.

Not a big fan of repair shops? :grinyes:

All jokes aside, you are right. Repair shops should indeed hold themselves to a high standard.

The story on ‘The Shop’ that I’m dealing with is a little different.

The following is ’The Shop’s version of their history with this car.

The Impala that I own was built to certain performance specs by ‘The Shop‘ for a customer.

The engine had blown at some point a few years back and, instead of replacing it with a factory LT1, ‘The Shop” offered to build a 383 stroker for the same price: forged internals, Edelbrock heads, ported intake, and 58mm throttle body (a little big as far as I know).

The stock transmission couldn’t handle the power and it too went the way of the stock engine. So over time, at ‘The Shops’s suggestion, the previous owner purchased various parts to rebuild the stock the transmission into one that could handle the power: heavy duty internals and billet servos and what not. “A step below a racing transmission” is how ‘The Shop’ described it.

Eventually, the same was done with rear end: 3.90 gears, Tom’s racing axles.

According to ‘The Shop‘, the car was dynoed at 350 rwhp and over 400 lb/ft torque.

Ironically, the suspension and the ignition system was left stock.

The car was eventually rear ended from the driver’s side. The driver-side tailight, the bumper assembly, the driver-side rearview mirror and part of the rear deck lid were damaged, along with a chink in the driver-side rear-quarter panel.

The insurance totaled the car.

The customer sold the car to the ‘The Shop.’

‘The Shop’ advertised the car on Craigslist. No one seemed to be buying it.

I called ‘The Shop’ and arranged for an appointment to see the car.

The car appeared fine overall. The driver-side door panel was in horrible condition.

I was not able to test drive it due to expired tags but we did go for a spin with ‘The Shop’s owner in the driver’s seat.

The car hauled.

I told the owner I would buy it if the car passed smog. The car passed just fine.

I paid for the car, signed the ‘Sold As Is’ document, and left the car for ‘The Shop’ to repair the damaged AC hose I mentioned in an earlier post.

I drove it home two days later and didn’t touch it for a week until I could get the registration done ( a cool $350).

I drove it to work a few days later and that’s when the head gasket went.

The only reason I didn’t march into ‘The Shop’ and unleash hell was because the owner of ‘The Shop’ is a customer at my Dad’s computer shop and my Dad thought of him as a good man - up until the head gasket went of course.

But, to be fair, even I have sold a car and certain things failed the very next day.

So I gave ‘The Shop’ a chance to work this out and we agreed to go half-half.

And now here we are…


I hope that fixing the PCV system cures what ails your BABY. Was the smell mostly from the engine compartment? If the tail pipe burns clean you are probably all right.

Yes, the smell seems to come from the engine compartment but I smell it inside the cabin.

I have not seen any tailpipe burns yet.

I will check out and replace the PCV system components based on the information j cAT provided about the hoses.


Keep us informed. The more we learn the more there is to learn.

Hopefully some updates by the middle of next week.

As always, thanks for the help…

While I am working on trying to fix the PCV system on the Impala, here are some links to interesting discussion on the LT1 PCV system.

They range from helpful to ridiculous.

Hopefully these will help someone or make good conversation…

http://www.z28.com/forum/showthread.php?t=72691 (http://www.z28.com/forum/showthread.php?t=72691)

fbody .com (http://www.fbody.com/lt1/297037)

ls1lt1 .com (http://www.ls1lt1.com/forum/archive/index.php/t-15390.html)

I'll be working on the car after work tonight and will have some updates real soon...

the pcv / crankcase vent was removed,,,possibly to reduce blowby gasses getting into the throttle body...I suspect an engine that was abused....sorry ....

the passenger side of engine is where the vent for crankcase should be into the valve cover, this then goes into the side /top of the throttlebody that was pluged in your picture...on the driverside into the intake manifold is the PCV location...then the hose from the PCV goes into the bottom of the throttle body under the air intake ,,,,hose hard to get at....

the lack of crankcase venting will cause the gaskets to blow out as pressures in the crankcase will do this....as well as any hoses/valve cover gaskets etc...a good running engine should have a slight vacuum in the crankcase...

with your engine running and hot I bet with the oil fill removed it smokes out of the fill hole pretty good..as it is now..


most likely they screwed up the re-build or did not properly break in the engine,,

So I went to NAPA today and the guy I spoke to basically confirmed what j cAT said: its either an abused or improperly rebuilt motor.

He suspects that either a piston ring or a piston is damaged and the air inlet valve on the right side of the engine was blocked off by the shop before sale as a quick fix.

But one would think that would have been an easy fix when the heads were removed for the headgasket job.

Another thing the guy ay NAPA mentioned was that if I put the hose back on, the morot would be gone in a month. Any thoughts on that?

Not to slam your NAPA guy but everyone who works a parts counter is a car guy/gal.
Good people but to some folks it is just a job.
IMO you should do a spark plug check. Seeing the coloration can show what condition that cylinder is in. To me if they are burning clean there is probably nothing wrong with that cylinder. While you have the plugs out you might as well check the compression of each cylinder. J cat & the NAPA guy may be correct but you should perform these basic checks just to be sure. Not knowing how the motor was broke in stymies your investigation. Even though the LT1 is a roller motor it should have been broken in with assembly lube & a quality dino oil with the proper zddp content. If the motor was broke in with say MOBIL 1 the rings and such will not seat properly because M1 is so slick.

HOE THE IDEAS HELP.

Not to slam your NAPA guy but everyone who works a parts counter is a car guy/gal.
Good people but to some folks it is just a job.

No offense taken! :biggrin:

I felt really down yesterday after talking to the NAPA guy. He is the second guy at a parts store who has told me that I may have been baited, i.e., ‘The Shop’ sold me a car with problems so I can keep bringing it back for repairs while they claim innocence.




IMO you should do a spark plug check. Seeing the coloration can show what condition that cylinder is in. To me if they are burning clean there is probably nothing wrong with that cylinder. While you have the plugs out you might as well check the compression of each cylinder. J cat & the NAPA guy may be correct but you should perform these basic checks just to be sure. Not knowing how the motor was broke in stymies your investigation. Even though the LT1 is a roller motor it should have been broken in with assembly lube & a quality dino oil with the proper zddp content. If the motor was broke in with say MOBIL 1 the rings and such will not seat properly because M1 is so slick.

You are right on all counts.

I was just so damn upset yesterday after talking to NAPA Guy that I practically gave up on any hope on the motor. Its bad enough being hasseled by cops while driving this car...

After I calmed down, I did some research and several forums suggested the same thing as you did: do a compression check.

While conducting my research, I also came across three other things that caught my attention: Envalve, the catch can, and a book on how to win a case in small claims court.

Apparently the Envalve is a PCV that replaces the stock PCV and, from what I vaguely understand with my limited knowledge, adjusts the vacuum so that all but the worst of the motors no longer experience blow by.

The other is a catch can that is meant to catch the oil that is shot out during the blow by and caught in a can to be reused. This idea came up very frequently and, according to those who built and used one, it works well.

Any thoughts or experiences on using either the Envalve or catch can?

I also gave ‘The Shop’ owner a call yesterday and mention that the metallic PCV breather and the throttle body were plugged off and he said he wasn’t aware of that. So I made an appointment with him so he can see for himself.

I think I’ll take somebody with me as a witness in case the owner makes any false claims. I will also ask him if he will pull the plugs and do a compression test in front of me. While I'm there I'll also ask if he remeber what oil was used to break in the motor, although I think I already know what answer I'll get...

As always NOVA, your ideas and insights are very helpful. Thanks for the help and support.

I have experience with motors like yours,,,,as my son had a vehicle with the same problem...well we or should I say I got the vehicle to go about 80,ooo more miles before it was sold for 400.oo....

this vehicle consumed 1 quart/400miles....with all of the oil being sucked thrU the Pcv VENT SYSTEM...

what is occuring is combustion chamber gases are now flowing down the piston past the rings into the crankcase....as the engine is operating the oIL gets vaporized...then the PCV sucks out this vapor excessive pressure...

this is a condition that you must attack at the source,,,these people did what they did to cover the defective engine ,,,,you should get your money back....this is fraud...and they are guilty of altering polution control devices....

WHEN YOU TALK TO THESE PEOPLE HAVE A WITNESS...

Hey All,

So here’s an update on what’s taken place since I called talked to NAPA Dude and called up ‘The Shop’ regarding the plugged inlet and throttle body.

On Friday I visited our local performance shop, Team C in Bellflower, California. I inquired about oil catch cans and they have one made by Moroso for eighty dollars. The guy who was assisting me checked out the car and he also said – like everyone else – the inlet shouldn’t be blocked off.

Unfortunately, I wasn’t able to go to ‘The Shop’ on Friday as I had planned but did go Monday evening with my uncle as a witness, as j cAT suggested.
It turned out they were already waiting for me.

We had to wait for a good half hour before the owner showed up from his trip to the local smoke shop.

When he came in, we immediately went out to the car and I showed him where the air inlet PCV and the throttle body were plugged off.

It was obvious that he was already in defensive mode when we arrived at the shop and, as expected the stories came tumbling out.

Right off the bat, he wanted to know if I had been keeping an eye on the oil level and what weight I had used. I told him I checked it every so often and was now using 10w30, instead of the 5w30 that was used in the last oil change. He said the 5w30 was too thin and that I should use 20w50. I reminded him that, when he sold me the car, he told me the previous owner was using 5w30 synthetic. He said the previous owner had recently come by and had mentioned that he had been using 20w50.

So the conversation turned to the PVC system. He said the valve covers are aftermarket valve covers the previous owner brought in to have ‘The Shop’ install them. The passenger-side cover had to be notched to accommodate the alternator bracket (this I was informed of when I bought the car).The original valve covers allegedly had no air inlet on the passenger-side (I was calling BS in my mind).

I told him that, after having spoken to several people, I have learned that this is part of the original PCV system and should not have been messed with. He wouldn’t give me a straight answer, instead reiterating that the previous owner brought in the valve covers to be installed and that is just what ‘The Shop’ did. And it was too long ago to remember any specific details now (he claims four to five years ago). The shop has no paperwork records.

When I pressed him some more about the air inlet being plugged off, he admitted that it could cause the vale cover gaskets to leak, but he could see the benefit of hooking up a hose between the inlet valve and the throttle body. He didn’t think the increased pressure in the crankcase could cause the head gaskets to fail.

So then we moved onto the infamous thermostat bypass/ fan wire hack job. I asked him why this was done and he said the fans are wired to run off the computer which had been tuned to run the fans at a very low temperature. If I installed a thermostat, it would cause the fans to run continuously because the engine would be warmer than what the computer has been programmed for. He said that ‘The Shop” always had a problem with the car overheating and finally figured this was the method since the engine is setup for reverse-flow cooling and running the engine super-cold allows for higher compression (he claims its up by .5 compared to stock LT1).He further mentioned that I can’t consider stock temperature specs because the engine is far from stock.

So basically, he’s sticking with his ‘we sold just the way it was’ deal.

I, on my part, will be hooking up the hose (the one I bought was too small for the throttle body) and changing the oil to 20w50 and watch what happens.

As of right now, the oil consumption seems to have dropped and I no longer smell any oil burning.

Perhaps thick oil is all that’s needed after all?

Stay tuned...