Questions and Answers

Jeep Cherokee: Gas In The Oil? Q. Oil leak near rear main, no surprise, but I think I am getting fuel in my oil. Is this caused by fuel injector clog or something worse? Oil leak does not concern me to much, car is a third vehicle drive 500 to 1,000 miles per year only unless its related to gas in the oil. 1992 Jeep Cherokee 4.0 liter 6 Cylinder 149,000 miles Fuel injection Thank you, Jerry

A. The only way fuel can get into the oil on your engine is through the cylinders. A clogged injector won't do it, but one that doesn't close completely will.

The fuel injectors face the back of the intake valves which point down. If an injector is leaking, and the valve is open, fuel can enter the cylinder and seep past the rings into the crankcase.

This can be confirmed by putting a fuel pressure gauge on the fuel rail and running the engine to get full fuel pressure. Shut the engine off and immediately pinch the fuel feed and return lines. If the fuel pressure drops, you have an injector(s) leaking into the cylinder(s).