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Gas in oil pan, oil on plugs 6-4

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14K views 12 replies 8 participants last post by  91RS  
#1 · (Edited)
Changed the oil for the first time since warranty ending, noticed a strong smell of gas in oil. Oil was very black, diluted and ran like water.

According to manual, engine oil should be changed when indicated by the engine oil-life computer. We have never gone by the computer and changed oil every 3-3,5k.

This was my first oil change so I would not have noticed this problem during the warraty period.

Today I changed the plugs. There has been a rough idle, stall, lurch, surge as first reported at 21,000 miles. We are now just over 50k and the idle has been getting rougher over the last month so I changed the plugs.

After letting the engine cool down a little, I pulled the stick and the oil level seemed good but on the low end between the hash, It smelled like gas again! I did not drain the oil because it is still clear and viscous.

I removed the first plug by the radiator, it looked good. I removed the next and it was good too. Then came the third and it had some oil on the threads. I figured it was normal. I proceeded to the fourth plug, and as I lifted it out a drop of oil dripped from it. The fifth plug was entirely coated, and the sixth plug near the firewall came out leaking oil all over. I don't know which side of the cyclinder the oil is coming from but the oil really smells like gas so I am assuming the two are mixing at some point.

Before replacing the new plugs I checked the gap on the old ones. They were all .043-.045, but I assumed it was due to the tips being worn down. The new plugs were ACDels with gaps at .042 just like the owners manual said.

The throttle seems more responsive and steady overall, but all of the old symptoms are still present. I am assuming there is a reason gas is getting into the oil, and oil pooling on the plugs?

Btw, no sludge or fouled plugs, no smoke from exhaust at any RPM, and no temperature or oil pressure issues.
 
#8 · (Edited)
I'll be replacing the valve cover kit today, I'll draw out a couple of plugs while I'm at it and check for oil again.

Could really use some advice, though.


1) Is there anything I might want to inspect when I get the cover off?


2) Are there bolt torque specifications anywhere online? I know I will be releasing quite a few parts during this task, valve cover, manifold, alternator, etc. If nothing else I could just measure the current torques with my wrench, but its such a pain in the a$$.:hissy:

Thanks fellas.
 
#9 ·
I would keep an eye on the oil in the plug holes before you replace the valve cover gasket because it's a PITA since the intake has to come off. I would get some good brake clean and just clean the holes out and then check it next oil change.

As far as the fuel in the oil, I would highly suggest getting an oil sample analized by Blackstone and see what they say. They will tell you if there is any water, fuel, coolant, etc. in the oil and how much and possible causes as well.
 
#12 · (Edited)
The oil on the plugs is coming from the valve cover I believe. I was not able to replace the cover gaskets after learing that I would need to discharge the AC. I spoke with someone and showed old plugs, I was informed that the plugs were not oil fouled and that they looked normal.

As far as the fuel in the oil, I would highly suggest getting an oil sample analized by Blackstone and see what they say. They will tell you if there is any water, fuel, coolant, etc. in the oil and how much and possible causes as well.
What is Blackstone, did a search and couldn't find it.


The injector might be leaking after shutting down and washing the fuel down the cylinder walls. Whatever is causing it I wouldnt be driving it until you fix it because not only will you scuff up the cylinder walls but you will also end up doing in your crank as well.
Cool!

Is the truck smoking at all? If it were bad rings, the truck would smoke. Could be like the guy above said about the injectors.
Nothing, no smoke. Maybe just my imagination. I would take it for diagnostic but evertime I do they just tell me nothing is wrong. And now my warranty is up I will have to pay them to tell me nothing is wrong, or worse, they will actually fix the problems now that there is no warranty.

I'm not playing that game. Besides I'm tired of sitting at the dealership for hours, being without a car, and then being told they can't recreate the problem.