Hello,

Alright this is my first time to post here so lets see if yall can help me. I have a 2004 Silverado 4x4 5 speed with 4.3L V-6. Check engine light came on and is throwing codes p0172, P0175 showing both banks are running rich. It also has a code for random misfires. I have replaced fuel pump, filter, regulator, wires, cap, plugs, MAF sensor, and both o2 sensors in front of the cat. Stilllll no change. You can feel it riding rough down the hwy and at various other times. Any suggestions? I was thinking i would switch out the regulator again and see if maybe it was a bad one i got from auto zone, then go from there maybe other sensors? Thanks.

 

Welcome to the forum. If all those new parts were for P0172/P0175, the first thing you ought do is to fire the shop that kept throwing parts at the problem. You might then want to get the fuel pressure checked AND fuel injectors tested.

 

My last Corvette had a like problem. It was a bad Injector. May not be your problem. The Vette eventually would not start.

 

Have you tried...... Change engine oil? chewed harnesses? bad gas?