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Gas in My Oil?

I have a 86 Cutlas Ciera GT. It has a new engine with about 20k on it. I have been getting the ocasional belching of black smoke and massive amounts of oil in the gas. I have some ideas of what could be the problem but don’t want to go into this blind. What would be the best way to diagnos the problem. Big thanks for any help.

First you said “gas in my oil,” then you said “massive amounts of oil in the gas.”

Make up your mind.

Gas in the oil and black smoke indicate an extreme rich condition. Leaking fuel injectors would be my first guess. If the computer thinks the engine is cold it would enrich the fuel mixture and could also cause this.

Massive amounts of gas in the oil is very bad. Can you define “massive amounts?”

Gas in oil is NOT good…and can seriously damage your engine. If there’s too much gas that’s not getting burned it will leak into the cylinders and cause a wash condition. This removes or dilutes the oil from the cylinder walls and can cause serious damage. Not to mention that any raw gas in the oil will dilute it…

Sounds like a leaking injector. Need to get this fixed.

In Fords a while back,
Gas in the oil was from a leaking fuel pressure regulator ( internally through the diaphram ) and the vacuum would suck the fuel in where you’d see it on your dipstick.

Oil in the gas ? that’s another can of beans.

This is probably a typo and my vote is for the leaky fuel pressure diaphragm that Mr. Green mentions.

One thing you should not do is continue to drive the car with heavily diluted engine oil or you can kiss your new engine goodbye.

Sorry about the typo. Gas in my oil would be the correct answer. It was parked because of this problem. I had grabbed an intake manifold with everything on it off a running car sometime back. It has the regulator, injectors, ignition box, ect. Should i just swap that out and see how it goes. If I had a internal problem such as rings, valve seals, head gasket I would definitly have other simptoms? After changing the oil you can smell the gas on the dip stick and see the level rising. Yes, massive! She is a beauty. Can’t stand to see her sit anymore. Big Thanks!

an '86 Cutlass Sierra isn’t my idea of a beauty. It is a pretty old and basic car. Now a '76 or '77 Cutlass with a 350 ci 4 bbl V8 well now that could be a beauty.

Massive amounts of gas in the oil is very big problem. Since this is a FI car with an old and relatively unsophisticated FI system you need a compete diagnostic workup of the FI system. Leaking injectors, or throttle body can cause this; excessive pressure from the fuel pump, or a faulty fuel pressure regulator can cause it as well.

If you don’t fix it soon, driving it like this will pretty much ruin the motor.

Have you ever seen a cutlass ciera gt? I have had the car 15 years and I’ve never seen another 86. I have seen two 87s. Beleave me I have looked for them. I know its just a k car but beleave me she’s a beauty. Its dark maple metallic with grey ground fx and spoil. All leather interior. Its not granny’s cutlass ciera. It was only produced 3 years and was produced in very low numbers.