[Jon01]

Originally Posted by JJAB

Ran into a friend that helped me out a bit and he happened to be a lot more GM versed(he is a Master ASE technician)LOL, than me. Well we took a closer look at the blazer. When the Blazer acted up it threw a fuel pump driver circuit fault code. He explained it to me like this: The pcm controls the amount of amperage through the fuel pump by controlling the fuel pump ground wire with a driver module in the pcm. The pcm checks the amount of current draw coming through the fuel pump to see if it matches what it asked the pump to do. If it doesn't match, it sets a code. The code sets when the blazer starts acting up. Since this is the second new fuel pump installed since installation, most likely there is something wrong with the control module portion of the pcm.

FYI, fuel pump is being operated through a relay!!


Please chime in and tell me your thoughts. Plan of action at this point is that we are going to purchase a new PCM and have it tuned.

Your friend is thinking of a returnless system that varies voltage to the pump rather than having a regulator/return line.