Oil has slight gas smell

[buck15]

Hey Guys, I have just checked my oil on the dip stick, which was replaced 2500 miles ago and noticed it has a gas smell to it. Is this normal? What would cause this?

[dparm]

Well it can be "normal" if the car is getting a lot of short trips where the oil doesn't come up to temperature. If the oil isn't getting hot enough, the fuel and moisture in the oil won't burn off. It's still bad for the car, though.

Could also be a leaky injector. Or blow-by. Or bad spark plugs causing improper combustion.

Fuel will dilute and thin-out oil, which is bad. Some oils can resist this better than others, but that's really just a band-aid.



I would take the car out for a long (30+ minute) drive on the highway and see how the oil smells afterwards. You could also consider an oil analysis to see just how thin the oil has become and how much fuel has gotten in there.

[ECS Tuning-Audi]

I would say it has more to do with a PCV issue rather than the oil not reaching operating temperature or a leaky injector.

Jason

[buck15]

I was talking to my local Audi tech, he said that our cars have a sensor in the oil that will throw CIL if there is a certain amount of gas in it. can any body confirm this?

[B6JoeS4]

I was talking to my local Audi tech, he said that our cars have a sensor in the oil that will throw CIL if there is a certain amount of gas in it. can any body confirm this?

Bullshit. Only sensors I know of are the pressure sensor on the oil filter housing, and the level sensor on the bottom of the pan.

[buck15]

[QUOTE=ECSTuning-Audi;6894823]I would say it has more to do with a PCV issue rather than the oil not reaching operating temperature or a leaky injector.

What are the symptoms for a bad PCV valve?

[dparm]

Heavy oil consumption is one.

[audivoodoo]

OP how do you warm up your car? Do you sit at idle alot? long periods of idling can also give oil that smell.

[buck15]

OP how do you warm up your car? Do you sit at idle alot? long periods of idling can also give oil that smell.

In the last two weeks I have more than normal. Question, it would not take much fumes of gas to make my oil smell like gas?

[ECS Tuning-Audi]

Oil should have a slight gas smell to it. Or like an "exhaust" smell. Which is normal.

Another symptom of PCV/poor crank case ventilation is if you can't remove your oil cap while the car is idling.

Jason

[redls1bird]

Easy answer. Praise science!

http://www.blackstone-labs.com/


http://www.blackstone-labs.com/what-is-oil-analysis.php

[dparm]

Let's not overthink it.

Go for a long drive on the highway at a constant speed (30+ minutes). This will burn off the majority of gas in the oil. Then drive as you normally would for the next week; check the oil again and see how it is then. Sometimes you'll just get some gas contamination from the dropping temperatures (car runs richer) or excessive idling.