A leaking fuel pressure regulator can cause your car or truck to be hard to start or die out. This may give a check engine light, also. It's a very common problem on many Chevy, Buick, Pontiac, and Oldsmobile 3.1L - 3.4L V6 engines. These are also know as the 3100 and 3400. Misfire codes P0300 and oxygen sensor codes will be stored in the computer memory. So, if you want to learn how to check your fuel pressure regulator for leaking gas on GM engines, then this video tutorial is for you.