98 Lesabre, need help...

I recently purchased a 98 LeSabre w/ 115,000 miles on it. Car belonged to a friend of the familys mother. Car has sit a quite a bit over the past year. I purchased the car and drove it for 200+ miles problem free and engine sounded as smooth as possible. However, last night while driving down the hwy I heard a knocking noise. I pulled over and looked the car over. When stopped the car would stumble like it was about to stall, oil pressure would drop and light up, and the volts would drop and light up. Car was not leaking any fluids, and there was plenty of oil up on the dipstick. I drove the car home nice a & slow. I originally thought the noise was coming from a pulley, so today I removed the belt and started the car, the noise does not go away. I checked all the pulleys, they all seem to be ok. Noise appears to be coming from the top half of the engine, maybe valve area. I drove it approx. 1 mile and it even quit making any noise momentarilt 3 or 4 times during the drive. Sounds more as it something it hitting/rubbing on something more than a knock. Also when the engine is cold, the oil pressure and voltage remain stable, only when the car gets up to operating temp. do they start jumping. If anyone has any ideal what this could be, please let me know. I am at a loss of what to work on next. Thanks

The voltage and oil pressure jump around at a steady speed or idle?, from here diagnosing as knock is impossible as you can imagine. Is the oil clean, not water or fuel contaminated?

Voltage & oil pressure only jump around when engine is warmed up to operating temp. and at idle. If the car is being drove they are both stable with no movement until you stop. They are also stable at idle if the car has been sitting and is cold. Oil was just changed 500 miles ago. It hasn't used any oil, and oil still appears to be new. (Looks like it was just poured out of the jug) No change in color or smell.

I recently purchased a 98 LeSabre w/ 115,000 miles on it. Car belonged to a friend of the familys mother. Car has sit a quite a bit over the past year. I purchased the car and drove it for 200+ miles problem free and engine sounded as smooth as possible. Thanks

Was the oil a fresh change? Does the car still have dexcool in it? How does that coolant look?

If you changed or do change the oil, look for coolant in the oil you drain out.

The extra slow idle could be an EGR not closing all the way or a coil giving a poor spark to 2 cylinders after the coils get hot.

Is there any possibility you could use a digital camera to make a video with sound of the noise and post it as an attachment here, if that works, or post it on photobucket.com and put a link to it.

There are many experienced readers who might be able to recognize the sound.

The oil was fresh changed. It was changes about 500 miles before I purchased it. Oil still appears to be can fresh with no change in color or smell. Car does Dexcool in it. Coolant still looks at it normally would and the coolant levels have not changed.

It may be a few days but I will try to get a video of the engine sound and post it for you to hear. I didn't make it home with the car, its about 25 miles away, so next time I go down to work on it I will take the camera.

Unfortunately it was the motor. Broken rod, and scared the crank. Luckily I was able to fine a 05 impala engine w just 60,000 miles on it.

Unfortunately it was the motor. Broken rod, and scared the crank. Luckily I was able to fine a 05 impala engine w just 60,000 miles on it. can i ask what kind of oil is in it?

If your asking about the engine that blew I have no ideal what kind of oil the previous owner used. They had it changed at a Valvoline quicklube last.

I put Penzoil 5w-30 (Dino) in the newly installed engine. Figure I will run it 800 -1,000 miles and then change it again. I run Penzoil Platinum (Synthetic) w/ Purolator gold filter in everything else I own. Not sure if I will try it in this engine or not since it already has 60,000 miles on it. I prefer synthetic but I am afraid of getting leaks since I don't know what was previously used in it.

New synthetics will not cause oil leaks.

New synthetics will not cause oil leaks.My last motor was nice and tightly sealed, no leaks at all. I put in Synthic and it leaked like a sieve. Leaked from every place the motor could leak from. Man did it leak.
This was a couple years a go. When does, "new" synthetic start?

Chris.

The new synthetics have had modifiers in them to help with seal issues for at least 10 years.

The new synthetics have had modifiers in them to help with seal issues for at least 10 years.Doesn't work on older motors.

I have changed to synthetic on a '96 Lumina (189 V-6) with 142K, a '95 LeSabre (231 V-6) with 124K, a '96 Sonoma (134 I-4) with 89K, three Fieros with between 90K and 138K, a 2001 Impala with 68K, an '88 Astro with 80K, and never had a leak. This was done with the OLD synthetic (Mobil 1) which did not include a special "high mileage" additive package. The Sonoma did lose a head gasket, but that was probably not due to the oil as much as the aluminum head eroding.

All TRUE synthetics (PAO, not the hydro-cracked Pennzoil, Quaker, and domestic Castrol crap) will do is to soften deposits and clean them away. If the sludge is preventing a damaged seal from leaking, the seal may leak. If the seal is not damaged, once the sludge is cleaned away and the elastomer is made pliable again, the seal will stop leaking. If the synthetic exposed a leak that's bad luck, but it almost certainly didn't cause it. I do know that synthetic tends to wick through the smallest openings, and I have found three leaking oil cooler hoses on various vehicles, but no seals, gaskets, or other joints.

Glad you have success. I'm 0-2 with switching. My friend switched and now leaks just as bad as I experienced.

Sorry, I didn't understand your definition of "cause." If you have no leaks at all, switch to synthetic and it leaks bad, it's not the oil that "causes" the leak.

Since this happens all the time, I didn't want to post on a forum that nothing will happen if you switch.

I wish I could change to synthetic. My friend and I, The mechanic I go to, and the guy on the radio experience it will leak. I'm stuck using Dino oil.

Chris.

I run synthetic with no issues... and have gone back and forth... Synthetics causing a motor to leak is a Myth... The reason they can start to leak is due to all the build up inside the motor being cleaned away.. But newer Dino oils also have better cleaning agents as well so if you have a seep its only going to get worse over time...

3800's love to leak in a few places no matter what oil you use... Rear main from time to time, More than likely to be the rear plate that houses the rear main and seals the back of the block... Oil pan gasket and or valve cover gaskets... One of these will leak during the life of the car no matter what oil you use...

My 95 Bonneville engine had 60k on it when it was installed... I have been back and forth with synthetic and Dino... I have had 2 common issues with it, Valve cover gaskets( $13 ) and oil pan gasket ( $30 )... I replaced those and to this day( Motor has 87,000 on it now ) the motor is bone dry...

My 03 Bonneville ran Kendall for the first 50ish k miles, I then went to Synthetic... It too is bone dry and now at 77,000...

The original motor in the van was changed to synthetic at 170,000 Miles, it too was dry and had no leaks... as well I ran my 91 Bonneville on Synthetic for many years starting at 80,000 miles and had no issues... never even replaced the oil pan gasket, no leaks...

Generally the seals and gaskets would have to be pretty bad to have any issues with synthetic..

You know I respect you very much. You have a lot of knowledge I've learned from you.

I think it's crazy to say thousands and thousands of mechanics, thousands of people have not experienced a motor leak, after switching to synthetic from dino oil. No leaks AT ALL, then in a few days, massive leaks.

Here is prof. Look at any forum on the internet, the same experience is all over the place.

**"I recently purchased a '96 TA with 95,000 miles on it. When I changed the oil I switched to synthetic and now have oil all over the place. Small bit behind the crank on the front of the block, the block itself is wet. The oil filter, drain plug, oil level sensor, and tranny are all covered in oil and it's been dripping from each of these as well.

Anyone have any ideas?

Thanks, Brian"

**"I have a high mileage (^ SS Impala, About 125000 mi), switched to syn oil. Leaked from the rear main, oil pan plug, level sensor, etc. I have repaired a few (not the main) and switched back to a hiogh mileage oil. It has helped a little. My big problem is the oil dripping on the convertor. Smells bad when you stop at a light and park."

**My car is not a GM car, but a friend with an older Z28 had a similar experience. My experience: In January 2009 I took my Audi S4 to a private repair shop. Sometime years ago, it had been switched from the synthetic oil it came with to non-synthetic oil.

In January, there were NO oil leaks--not a drop. The mechanic who replaced the timing belt and water pump in January decided without input from me to switch it back to synthetic. Very bad move! Within a couple of days, the left head gasket began leaking oil onto a hot exhaust manifold. It was smoking visibly and delivering a bad smell into the car. By the time I could no longer put up with it in May, it needed leaks repaired in FIVE places, including the seal behind the timing belt. Oil had leaked onto the new timing belt, necessitating its replacement. (So there was either leak there before the timing belt was replaced in January, or the mechanic missed it and it wasn't dripping -- an unlikely circumstance. But it did begin leaking afterward. That strikes me as a very telling detail.)

Repairs at the dealer in May came to $2,600 for all the leaks and the new timing belt. Ouch! I have subsequently done considerable research on the web about this phenomenon because I considered suing the garage. Again -- it went from not a drop of oil seepage to leaks in five places including the very one at the place the mechanic replaced the timing chain. That is a very dramatic and sudden change."

Chris.

No offense to you at all Chris...

But do you believe everything you read? If this was 100% true we would not even have Synthetic Oil on the shelf..

Now I want to look at this a little..



**My car is not a GM car, but a friend with an older Z28 had a similar experience. My experience: In January 2009 I took my Audi S4 to a private repair shop. Sometime years ago, it had been switched from the synthetic oil it came with to non-synthetic oil.



In January, there were NO oil leaks--not a drop. The mechanic who replaced the timing belt and water pump in January decided without input from me to switch it back to synthetic. Very bad move! Within a couple of days, the left head gasket began leaking oil onto a hot exhaust manifold. It was smoking visibly and delivering a bad smell into the car. By the time I could no longer put up with it in May, it needed leaks repaired in FIVE places, including the seal behind the timing belt. Oil had leaked onto the new timing belt, necessitating its replacement. (So there was either leak there before the timing belt was replaced in January, or the mechanic missed it and it wasn't dripping -- an unlikely circumstance. But it did begin leaking afterward. That strikes me as a very telling detail.)


Lets see, the water pump was replaced... Hmm the car is at the shop .... Now the question is was it there for a Timing belt and the water pump was replaced just because? Or did the guy run the car hot / Very low on coolant requiring a new water pump as the seals crapped the bed and while there the timing belt was replaced..

Lets be clear here, Dino or Synthetic is not going to cause head gasket issues, nor is it going to cause the head gasket to leak oil.. The only way this is going to happen is if the engine was run hot enough to fry the head gasket, or it ran hot enough for the head to warp distorting the head thus distorting the head surface causing the head gasket to not seal correctly, at this point its very possible to leak oil...

My gut and my Brain say that this particular engine was run hot due to being run low on coolant damaging the head / head gasket... I would also hazard a guess and say that this is of no fault on the mechanics part..

Now I have to question if the guy even knew what he was talking about... If this was relating to the Valve cover gasket, the rubber seal used for them will degrade over time, there are rubber plugs in the camshaft area that sit in the head, looks like a half circle, this plug of sorts will also degrade, and if it cracks it will piss oil all over the place... Dino or Synthetic will not even matter here.. That rubber plug over time will be as hard as a rock...

Its funny, I even run Synthetic in my Push Mower, as well as my riding mower( it has forced lubrication )... Those don't leak either...

Looking at the posts for the LT1 Chevy V8's... We have no idea how they were treated... There are seals or crush washers on the oil pan, these should be replaced from time to time no matter what... If the oil level sensor leaks with synthetic you have some serious issues... The oil filter leaking, thats the best one I have heard yet.. Once you clean the sealing surface and then install the new filter, its not going to leak no matter what you use.. The guy with the 96TA had a bad rear main from the word go...

I really don't know what to tell you or say... I do not agree with the Myth that Synthetic will make the engine leak.. I would not recommend using it in a 30 year old engine, and would tell you not to waste your money if an engine had 250,000 miles on it, I would tell you to keep using the Dino...

Synthetic is good and well worth using, I use it and will continue to do so...


Chris I understand what your thoughts are, and I understand why.. But we are going to Agree to Disagree...

Some of the time, this is why guys like me get sick of working on cars, and at times even hashing out Myths..

Did intake gaskets on a 3100 V6 for a lady... We did it cheap too, all parts and fluids included.... Car ran awesome.. Hers was leaking internally and we caught it just in time... A week later the starter went out and we were blamed for it and told that we caused it... We had told her we noticed that her started was going to be short lived as it was not functioning properly... We were the ones who told her to keep an eye on it... I found out later through the grapevine she took it to a local shop, and had it looked at and again was blaming us for the starter failure.. The Mechanic there told her that " They did a beautiful Job with the intake gaskets ", Your starter failure has nothing to do with the work they performed " There is always someone out there trying to place blame... For the 2 guys that posted about their issues, I feel that they are trying to place the Blame... I can just about smell it...


Chris, I have no problem with you, you and me have differed in opinions here and there, But if we didn't have different views or opinions what would we have...

BTW Thanks for the Props

Hay, we agree!!! I know what your talking about.

I had a business fixing Computers. I would go and trouble shoot, get rid of a virus. I'd have their totally screwed up computer up and running. A couple weeks later they would call up and say I wrecked the computer. I would go over and they would have another, unrelated problem like a HD failure. "This didn't do this until you worked on it."

What do you think happened to my car? No leaks at all, when I switched to synthetic, massive leaks. My friend also?

I ask, because I want to use synthetic, but experienced massive oil leaks right after switching (no interest in blaming anyone). So did my friend and millions of others. I don't want to use the high millage because it doesn't stop swelling.

I was reading some more. One article looked like it was pretty well knowledgeable, but not sure when I got to this part;

"Conventional oils have solvents that stick to gaskets and seals and often cause them to swell a certain way. These gaskets and seals have been used to the same oil for years and the switch to any other type of oil (whether it is to a different conventional oil brand, or an upgrade to a synthetic) may be harmful. The oil you change (or upgrade to) will also have solvents and additives, different from the original. So in other terms, the changing of oils could result in oil leaks and/or a once small oil leak becoming bigger due to the reaction the seals and gaskets will have to the change (not because of the oil itself). If you think that this might be the case for you (i.e. if you have an older car using conventional oil), it’s recommended that you not try synthetic oil until you have an engine (or new car) with relatively virgin gaskets and seals that will be able to acclimate much more easily to the chemical changes of the newer type of oil."

My new-used (111,000 mile) motor we put all new gaskets on. I've had dino oil in it for a year now (changed it about every 4,000).

Maybe I should of tried Synthetic when I got it running? (We didn't because the mechanic has had same experienced as I).

Maybe I did something wrong on my motor that leaked? What could it of been?

Chris.

Sorry for asking another question before completing the other one, but what type of cam/lifter configuration does the 3800 have?

Any truth to the second paragraph:

"The problem that most people encounter when switching a high mileage car to synthetics is due to the detergents in the synthetic oil. The conventional oil "gunk" accumulates around the gaskets and other places, often times preventing leaks. The synthetic oil begins to remove this "gunk" and things like oil pan gaskets, main seals, and valve cover gaskets beging oozing oil.

Another thing to consider is based on the year of your vehicle and the type of cam/lifter configuration. A roller cam system works fine with synthetic oil. However, with the removal of zinc from engine oil over the last few years, many flat tappet cams have been unhappy with this change. My personal opinion is that flat tappet cam engines need a zinc additive even after break in. Most synthetic oils don't contain enough zinc and arent additive friendly."

Chris.

All Buick 3800 V6's are Roller Lifter engines or as some would say a Roller engine..

For a Conventional Lifter( Flat Tappet Lifter ) this may be an issue and could cause cam lobe and lifter face wear, the lifter face should be flat, but some of the newer oils can cause the lifter to become concaved instead of flat or wear down the cam lobe... This is not a problem with the 3100-3900 Chevy V6's, or the Buick 3300 and 3800 as these are all roller engines...

as well the older Vin 3 3.8 Buick V6's( 86-88 ) were also roller engines..

Some of the newer 3800's will have issues with the rear main plate leaking, oil pan gasket and or valve cover gaskets... These are all common with the 3800 series II engines... I was mostly luck with my first series II 3800... This engine stayed extremely dry though its service life, and that was mostly with Synthetic from 70k on... I ran this motor to 161,000... Car was an early production 95 built in late 94... I had one of the very early Series II 3800's... In that time I install 1 oil pan gasket, 1 set of valve cover gaskets, Lower intake gaskets.... Engine was quite dry when I pulled it at 161k... For whatever reason this engine never ran quite right... But having the car loaded to the gills and still getting 31 Mpg with the AC on for my 1000 Mile stretches was enough for me to leave it be..

When I pulled the motor down I found that it was assembled poorly at the factory.. Gaps were in some not so friendly places... Only one cylinder had the gaps pretty well staggered.. Motor always burned oil too, but the time it got to 150k it was using 1.5-2 Quarts in less than 3000 miles... Not sure why, but cylinder 4 had really bad piston slap...

My 06 3800 III in my van does not burn a drop... I think that motor has 60,000 on it now... And modded for more power and torque... Still does not burn a drop...

I do have a little seepage at the lower intake seals, but thats my own fault for rushing... Took 20,000 miles to make it show up tho... I will cure that soon as I plan to install Comp Cam lifters, Pushrods, so i will install the aluminum GM gaskets on the motor and seal the " install dry " gaskets...

I did the intake gaskets for a guy on a 90 Buick LeSabre... This was a couple of years ago... Saw him recently and he showed me how dry the engine still was... He told me I was dead right with what I did... I looked and sure enough the engine was as dry as a Bone... If you have not noticed, I hate leaks, they drive me crazy... If any of my cars leak on the ground I suddenly develop OCD....lol


I am interested in what gaskets you replaced on the motor...

I have to look at the paper to remember for sure. My friend knows how obsessed I am with oil leaks. When a mechanic works on my car, I ask them to wash there hands before they touch it. :)

I think there is a direct correlation between what a person is on the inside, as it is with what it looks like under the hood.

My engine compartment is like new.

I know we changed the valve covers, water pump, front and rear mains, upper and lower intake, oil pan.

I quickly got a little front seal leak, and an intake leak. Honestly, this pisses me off quite a bit, not just because I have to do it over again, but because I have a leak.

The intake I found by accident when I took off the air box (replaced the screen in the TB).

Not sure what's going on, I don't lose any antifreeze. Any ideas? Here is a photo of the leak. I was at a friends driveway and we where running out of daylight. We didn't have any way to look under the pipe to see exactly where it was coming from.
http://i995.photobucket.com/albums/af78/happydog500/intake-1.jpg

That very much looks like Coolant... You may have a leak at the throttle body or a plate that resides under the Throttle body...

Has the Upper intake ever been replaced?

Yes, got the new, updated one and a smaller pipe.

I have another thread about a problem with this motor since we put it in. Drives and accelerates good, except when I give it lots of gas, like passing. The RPM's go up, but I don't have the acceleration like I used to (symptoms are just like a clutch slipping but it's not).

Could this leak be causing that? If it leaks, why no coolant loss?

Chris.

I'll tell you what Chris, we will have to hop on the phone and talk soon... By all rights your car should run great...

Just realized you are on the other side of the nation... As far from me as you can get...LOL

By all rights your car should run great...LOLSo if your Throttle Body leaks, it should run great? I was hoping this might be the problem.

Chris.

The junk under the throttle body area looks like coolant goo... Not sure whats leaking but there isn't much there than can leak.. If you are using no coolant then I am lost... And using no coolant means you can't be burning it, so yes the car should run good..

Too bad you are too far away, otherwise I'd say let me look at it..

I think you should take a drive over anyway. It would only take a few days. It would be a nice adventure for you.

Chris.