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97 K1500 fuel pump and engine issue


bbullsj
11-23-2015, 05:21 PM
I was driving to work and my 97 K1500 with the vortex 5.7 was running fine. It hesitated a couple times during light acceleration after less than 3 miles of driving it. I got work, turned it off and by the time I left, it started up fine but then had the same issue within a couple miles. The next morning I had a check engine light and when it happened and I decided to turn the truck off and start it back up. It would not start. I disconnected the battery thinking to clear the CEL and reset the computer but nothing. After 45 minutes of trying I finally held the gas pedal to the floor while cranking and it sputtered to life. It drove like crap, and would not idle at a stop.

I checked fuel pressure and with the key turned on it went to 60psi but within 3-5 seconds it flatlined. I also noticed more oil than usual that had leaked from the truck. The rear of the lower intake has been seeping for about 6-7 years, just hadn't replaced the gaskets yet. I checked the oil level and it was at the top of the fill line, which I found odd because I hadn't topped it off in a while so it should've been low. I check codes with a Tech2 and found both bank HOS2 codes and 2 coolant temp sensor codes. (like an idiot I didn't write them down and erased them. I put a new fuel pump and assembly in it and a new coolant temp sensor. The truck started up kind of rough but once the gas pedal was pressed once it idled and ran fine. It runs great now, no smoke, no hesitations but still starts rough and sounds like it is missing until you hit the gas quick once and then it's fine until you shut it off.

I filled the gas tank up and then drove it around a little bit. I drove 70 miles running errands before I got back home and had burned through 3/4 of a tank (25 gallons) of gas. I have no idea where it's going! It isn't burning it and i'm not leaking any from the tank or lines. I let it sit a day and someone suggested that it could be going past the rings and into the crankcase and that's why it's leaking more now. Thinning out the oil and getting through the gasket easier. Also makes sense because after I let it sit for a day i check the oil level again and it was an inch down from the top. If that much gas was getting past the rings wouldn't I see smoke coming from the tail pipes from unburnt gas? I'm not sure what to check next and with winter coming can't be without the 4x4. The truck has the original engine and it has 196k on it. I know the engine is worn and i've been working on getting it replaced but now I feel almost like I have to.

So, bad rings? Stuck open injector or poppet valves? Any directions of what to check next would be of great help.

maxwedge
11-23-2015, 06:19 PM
Sounds like the injectors or spider/regulator under the upper intake iis leaking. Common issue on the Vortec.

rhandwor
11-23-2015, 06:22 PM
I would retest the fuel pressure the regulator maybe going bad to start vacuum can suck in gas with a blown diaphram. Leaking intake gaskets also cause problems.

j cAT
11-24-2015, 07:54 AM
""I checked fuel pressure and with the key turned on it went to 60psi but within 3-5 seconds it flat lined "" well if that means 60 psi then rapidly drops to zero that means unregulated fuel dumping into the engine with what you say on the other observations. my guess is the regulator/injector assy defective. runs ok above idle but not at idle too much fuel and oil being diluted creating your oil leak to increase much more .. as was mentioned these fail , common .

bbullsj
11-24-2015, 06:49 PM
So I think will almost 200k on a never touched engine I'm probably looking at the injection system is bad. I did some more reading about what would dump so much gas into the intake and like rhandwor said, the diagram could be defective and dumping gas into the crank case. Hence the reason my oil level was high and why more oil is leaking out, because it's thinner.
I did a lot of reading about the upgrade from CSFI TO MPFI and it looks like that migth be the way I go. Has anyone heard anything bad about that swap? I've seen them sold on tons of sites but it looks like everyone sells the Delphi one. Is there any seller that would be better to purchase from?

j cAT
11-25-2015, 07:48 AM
So I think will almost 200k on a never touched engine I'm probably looking at the injection system is bad. I did some more reading about what would dump so much gas into the intake and like rhandwor said, the diagram could be defective and dumping gas into the crank case. Hence the reason my oil level was high and why more oil is leaking out, because it's thinner.
I did a lot of reading about the upgrade from CSFI TO MPFI and it looks like that migth be the way I go. Has anyone heard anything bad about that swap? I've seen them sold on tons of sites but it looks like everyone sells the Delphi one. Is there any seller that would be better to purchase from?

http://www.1aauto.com/multiport-fuel-injection-conversion/i/1afin00022?f=507234&y=1997 200K that's good on this old truck of the rust belt.

bbullsj
11-25-2015, 02:57 PM
I might not be able to start working on fixing it for about 2-4 weeks. Will it hurt the engine to sit there with gas residue all over inside the engine? Should I drain the oil and put in some fresh stuff and then crank it over a bunch with the fuel pump relay out? Or should it be fine?

j cAT
11-25-2015, 05:07 PM
I might not be able to start working on fixing it for about 2-4 weeks. Will it hurt the engine to sit there with gas residue all over inside the engine? Should I drain the oil and put in some fresh stuff and then crank it over a bunch with the fuel pump relay out? Or should it be fine?

I would drain the oil out .. disable the fuel pump.. crank it a few times oil drained .. then add fresh oil/filter.

remember alcohol fuels are water based .. using conventional oil this would then create sludge deposits not good for the lifters.........

bbullsj
11-26-2015, 02:03 PM
Well the part is ordered and on its way. I won't be around the truck and or be able to drain the gas/oil mixed oil from the engine for about a week. Probably run a really good engine cleaner through and do a couple oil changes after I get it running again?

j cAT
11-26-2015, 05:01 PM
Well the part is ordered and on its way. I won't be around the truck and or be able to drain the gas/oil mixed oil from the engine for about a week. Probably run a really good engine cleaner through and do a couple oil changes after I get it running again?

post back how you made out .. good luck .. if the truck is not rusted out keep it as long as possible . new trucks are low quality not long lasting.

Schurkey
11-27-2015, 04:59 PM
I won't be around the truck and or be able to drain the gas/oil mixed oil from the engine for about a week.
No problem.

Probably run a really good engine cleaner through and do a couple oil changes after I get it running again?
Don't bother. Dump the contaminated oil, change the filter, put in clean oil. Done.

bbullsj
12-10-2015, 04:15 PM
I started to take things apart and here's what I've found. I've also found some pitting on the intake coolant gasket surface. It doesn't appear to be too deep but there is some there. Is there anything I could or should do about it?

bbullsj
12-16-2015, 04:15 PM
Got it all back together and gave it a good test drive and it runs pretty well. A couple things that concern me. Before this all happened when I would cold start my truck it would have a really nice "bark" so to say when it first started up. It does not have that now. It almost sounds like it rolls out of bed instead of jumping like it used to. Anything I can check to find out what might be causing that? Also, once it shift into overdrive, at about 45 mph and with low load on the engine it has what feels like a dead miss. Not a stumble but for a second it's like all the power is being cut and then it kicks back in. From what I can tell so far it only does it once after it gets into overdrive and then its fine. As soon as it shifts down a gear for any reason and then shifts back into overdrive (slowing down and taking back off or downshifting to speed up) it will do it again. Any ideas on what to check? I do have a Tech 2 available to me. I used it to adjust the cam retard to 0 degrees.

I know all the computer will have to relearn their parameter so maybe it's that? Doesn't seem right though.

j cAT
12-16-2015, 04:36 PM
Got it all back together and gave it a good test drive and it runs pretty well. A couple things that concern me. Before this all happened when I would cold start my truck it would have a really nice "bark" so to say when it first started up. It does not have that now. It almost sounds like it rolls out of bed instead of jumping like it used to. Anything I can check to find out what might be causing that? Also, once it shift into overdrive, at about 45 mph and with low load on the engine it has what feels like a dead miss. Not a stumble but for a second it's like all the power is being cut and then it kicks back in. From what I can tell so far it only does it once after it gets into overdrive and then its fine. As soon as it shifts down a gear for any reason and then shifts back into overdrive (slowing down and taking back off or downshifting to speed up) it will do it again. Any ideas on what to check? I do have a Tech 2 available to me. I used it to adjust the cam retard to 0 degrees.

I know all the computer will have to relearn their parameter so maybe it's that? Doesn't seem right though.

The 45MPH issue would most always be the transmission lock up solenoid. I would put a bottle of transmedic transmisssion conditioner run it a few hundred miles then drop the pan and replace filter fluid.

ONLY USE DEXRONVI NOT DEXRON III................

ENGINE SHOULD NOT BARK . should start quiet and smooth .

j cAT
12-16-2015, 04:39 PM
I started to take things apart and here's what I've found. I've also found some pitting on the intake coolant gasket surface. It doesn't appear to be too deep but there is some there. Is there anything I could or should do about it?

the use of marine tex works with pitting. intake does not get 400 plus deg f. I have used this product before on damaged metal with seal surface corroded [boat engine]..

bbullsj
12-16-2015, 06:53 PM
I feel like that's not a decent answer because I didn't have any trans problems before the repair. Is that something that can be caused by the trans economy relearning? Maybe it's a common problem with 4l60e's and I've just never had to work on one other than mine?

j cAT
12-17-2015, 07:06 AM
I feel like that's not a decent answer because I didn't have any trans problems before the repair. Is that something that can be caused by the trans economy relearning? Maybe it's a common problem with 4l60e's and I've just never had to work on one other than mine?

45 MPH is why this is most likely the problem . don't know what your tranny fluid is or condition or what your servicing schedule is but, if there is DEXRON III USED IN THIS TRANNY THEN fluid/filter servicing should be done less than 40 K miles.

dexron III turns to acid after 20K miles the more miles the greater its acidic level increases. this is why when using this NOW removed GM fluid spec is no longer used by GM. fluid turns gray , that is the metal ,that is eaten.

bbullsj
12-18-2015, 07:00 PM
Could I just buy a new TCC solenoid and replace the bad one or is it the fluid that is doing it? A new sensor is $35. Do you have to drop the valve body to replace it or just the pan and filter? Is the Dexron VI compatible with that tranny?

j cAT
12-19-2015, 09:22 AM
Could I just buy a new TCC solenoid and replace the bad one or is it the fluid that is doing it? A new sensor is $35. Do you have to drop the valve body to replace it or just the pan and filter? Is the Dexron VI compatible with that tranny?

Again dexron III is NOT the proper fluid for your vehicle or any other GM transmission. this fluid is not an approved GM fluid , this was done by GM in 2006. This was done by GM because this defective fluid caused them to go into bankruptcy . had huge costs on the defective fluid .Dexron III is not synthetic. dexron VI is synthetic.
your fluid is now dexron VI. that is the correct fluid.

I have used mobil synthetic transmission fluid since 2000. this is before dexron VI existed. its called dexron/merc tranny fluid synthetic.

CALL UP THE DEALERSHIP PARTS DEPARTMENT THEY WILL TELL YOU DON'T BELIEVE WHATS STATED ON THE INTERNET !
Because GM is in the vehicle selling business they do not gain by you operating a vehicle they make longer than 120K miles. This is why this change was never reported to the owners it was aTSB. Top Secret Bulletin.

BEFORE YOU DO THIS YOU USE THE TRANSMEDIC TRANSMISSION TREATMENT FOR A FEW HUNDRED MILES.

then you drop pan replace fluid and filter. wash the pan so its clean. since the TCC does work but not properly this may be due to BAD fluid/filter.

so do that first .

Then the sludge will be loosened so that when you do the fluid servicing it will be cleaned.

after that is done and its cleaned inside drop pan again and replace the TCC valve body and solenoid if its required .

what are your tranny fluid servicing intervals ? what fluid have you used ?

your comments if this was never done before by you have a transmission shop do the work . make sure they use the dexron VI not the dexron III.. tranny shops still use dexron III because it insures continued repair work. also this fluid is practically free.
DEXRON VI COSTS $8-10 A QT..

bbullsj
12-19-2015, 09:35 AM
I have been using dex/merc tranny fluid, but not Mobile1 brand. I believe it was Valvoline. I don't remember when I changed the tranny fluid last but I'm sure it could stand to be done. I don't drive it a whole lot and when I do it's to town and back (30 miles round trip). I will try the transmedic and then a fluid and filter change.

j cAT
12-19-2015, 09:43 AM
I have been using dex/merc tranny fluid, but not Mobile1 brand. I believe it was Valvoline. I don't remember when I changed the tranny fluid last but I'm sure it could stand to be done. I don't drive it a whole lot and when I do it's to town and back (30 miles round trip). I will try the transmedic and then a fluid and filter change.

remember if it says its synthetic fluid and is GM dexron VI spec then it is the correct fluid. I still use the older synthetic fluid for GM transmissions because I did not want to change the fluid synthetic types so I stayed with mobil synthetic for GM transmissions. never had a problem still run these vehicles 1996/2000 .

bbullsj
12-19-2015, 10:24 AM
Does it have to be synthetic? So, I can put dexIII synthetic or dexVI non synthetic or synthetic?

j cAT
12-19-2015, 01:37 PM
Does it have to be synthetic? So, I can put dexIII synthetic or dexVI non synthetic or synthetic?

dexron VI is synthetic . mobil synthetic dexron/merc is synthetic that is what I have used for many years to avoid the dexron III damage I knew before GM admitted this defective NON SYNTHETIC FLUID fluid.

Just go to the auto parts store and buy 5-7 qts of the dexron VI and get a new filter shallow pan or deep pan with a rubber pan gasket . torque the pan gasket to 7 ft LBS,

some trucks come with a shallow pan. my car has the 4l60 shallow pan the truck has the deep pan. you must get the correct fillter or issues on fit /it may fall of if the shallow filter is used in the deep pan . deep pan takes 1.5 qts more fluid.

bbullsj
12-19-2015, 01:43 PM
Not to go on the cheap side of things, dexVI is $7 a quart and I found Mobile1 full synthetic for $2 a quart. It was on clearance at AutoZone. Would I be fine using the Mobile1?

j cAT
12-19-2015, 01:52 PM
Not to go on the cheap side of things, dexVI is $7 a quart and I found Mobile1 full synthetic for $2 a quart. It was on clearance at AutoZone. Would I be fine using the Mobile1?

I did not see this at my auto zone. this is what I use https://mobiloil.com/en/automatic-transmission-fluid/synthetic-atf this costs me $8/QT at another store some charge $9.79 a QT. if you can get this for $2 then that is a great deal. I will have to call my store to see if this is also being discounted.

I called up the AZ stores near me NO discount $10... a QT......I normally use another store where I get a discount on the fluid. AZ is too expensive.

bbullsj
12-19-2015, 02:18 PM
That's what it is. I guess I'll use that then and I'll go back and buy all they had.

bbullsj
02-24-2016, 06:31 PM
So I ran the trans medic fluid for about 200 miles and then did a drain and fill along with a filter change using Mobil1 ATF. I also purchased a TCC solenoid from GM and replaced that while I had the pan off. For about 50 miles the tranny shifted great but now with about 200 miles, it has the same issue. It won't do it if it is cold, the longer I drive the truck the worse it gets until it drops out and then back in like it did before. Any other suggestions?

bbullsj
07-24-2016, 10:58 AM
So after messing with for a very long time I got the new injection system warrantied out and everything is working fine like it should be. Possibly a bad part, i'm not sure but it's running great again with no issues. There were no issues with the transmission, it was all with the new injection system.

j cAT
07-24-2016, 12:03 PM
So after messing with for a very long time I got the new injection system warrantied out and everything is working fine like it should be. Possibly a bad part, i'm not sure but it's running great again with no issues. There were no issues with the transmission, it was all with the new injection system.

so the injection was interfering with the tranny operation ?

how does the tranny upshift now when cold . when going into reverse from D does it engage quicker with the synthetic ?

bbullsj
07-24-2016, 12:09 PM
Yes, it was. I haven't noticed anything different with the trans after switching fluid.

j cAT
07-24-2016, 08:00 PM
Yes, it was. I haven't noticed anything different with the trans after switching fluid.

the synthetic will create faster pressure than the dexron III non synthetic fluids.
surprised it did not shift faster as I had observed. when it gets cold out you will notice it most likely.

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