What Are the Causes of Gas in an Oil Pan?

by Stephanie Ellis

When you are changing the oil in your vehicle, one of the worst things to notice is the smell of gas in your oil pan. It means that gasoline is somehow making its way into your engine's oil, a problem that can cost hundreds of dollars to repair.

Badly Adjusted Carburetor

Blackened areas on your spark plug can indicate a badly adjusted carburetor.

A badly adjusted carburetor can send too much gas into the carburetor, and the overflow will eventually wash down the cylinder walls and into your oil pan. This also tends to foul the spark plugs. Thus, one way to check for this problem is to pull one of plugs and look for blackening on it.

Faulty Fuel Pump

Older vehicles may have a faulty mechanical fuel pump.

Cars that are more than ten years old usually have mechanical fuel pumps. The fuel pump is attached to one side of the engine; if you notice fuel leaking from the connection between the two, your fuel pump has almost certainly failed. Unless you are an expert home mechanic, fixing this problem should be left to the professionals.

Misfiring Cylinder

A stuttering or knocking sound can help diagnose the problem.

If your vehicle's engine is running with a stuttering or knocking sound, it is possible that one cylinder is not firing correctly, which leads to gas condensing in the faulty cylinder and draining into your oil pan. Accurately diagnosing this problem requires some specialized testing equipment and needs to be done by a trained mechanic.

Blown Head Gasket

Driving with a blown head gasket can ruin your car's engine.

The gasket that sits between the engine block and cylinder head can "blow," leading to coolant leaking into the oil or exhaust fumes being pushed into the coolant system. Driving with a blown head gasket can easily ruin the engine, leading to costly repairs. Your mechanic can run a compression test on your engine; if there is a leak in the head gasket, the compression will be lower than expected.

About the Author

Stephanie Ellis has been a journalist since 1987. She began her career working at a small-town newspaper, but in the years since she has been published in outlets from "The Chicago Tribune" to CNN.com. She holds a Bachelor of Arts in communications from the University of California, Los Angeles.

Photo Credits

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