Fuel Smell in Oil

1995 Monte Carlo 3.4 DOHC

Changed the oil today and noticed it smelled a bit like gas. I have also been getting poor gas mileage. The car does sputter and stall when cold, but not when hot. I have been told to change the intake manifold gaskets, and I will. BUT, is the leaky intake gasket the source of all my problems, or just the rough cold idle?

Steve

Reply to
Steve Mackie
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You could have a head gasket problem and/or leaking fuel injector. I don't see how the intake manifold gaskets would cause gas to get into your oil. Also, with fuel injection, a fuel injector could be leaking out fuel after the engine is shut down, causing the fuel to build up in the cylinder, and then leak past the rings into the oil. I just had a fuel injector and head gasket replaced on my '95 Cavalier. It used a lot of oil (head gasket) and smelled of gas after the engine was shut down (injector).

David

Reply to
D Lawrence

The intake gaskets are a problem for the 3.4 as well?

I don't see how it could be causing the gasoline smell either. How many miles on this engine? Blowby shouldn't be that big of a problem yet unless it's been around the world a few times (high miles).

Another possibility is a O2 sensor could need to be changed. It'd seem that if it was rich to the point of getting gas to the oil you'd have a check engine light on.

But I have heard that changing the O2 sensor almost always helps gas mileage once the old has been in there for a few tens of thousands of miles.

You could perform a vacuum check with a vacuum gauge to check for vacuum leaks. You can use a fuel pressure tester to see if the line pressure leaks down quickly after shutting off the motor (it should not). Could be a faulty injector. But of all the fuel injected engines I've ever ran, I've never ever had any trouble out of a single injector.

Reply to
Clem

So I hear....

173,000kms (approx. 107,500mi)

No check engine light, but I could get the O2 readings checked out can't I?

I have to get my hands on a fuel pressure gauge.....

Steve

Reply to
Steve Mackie

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