IASilverado

Well that didn't fix the problem. I replaced the fuel line pressure sensor and also cleaned the ground located under the drivers door. I also checked the two grounds located in the front corners of the dash and they looked fine. For some reason when my alternator switches to the lower amp setting around 12.6V and I give it moderate acceleration I get a cel with p2635 code. Anyone have any other ideas?

Ok thanks I will look into that. Are the schematics posted on this site anywhere? Looking for the location of that ground. I'm assuming it is close to the tank/spare tire and grounded to the frame.

Hi guys I'm new to the site. I have been doing some searching to try and diagnose my problem. I have a 2017 Silverado 1500 and I keep getting a 2635 code. It's out of warranty so I am trying to figure it out without taking it to the dealer. It was at the dealer a few weeks ago for this problem and they replaced the fuel tank pressure sensor and the EVAP purge valve. I also ordered a fuel line pressure sensor and will be replacing that in a few days. I can clear the code and it will come back a few days later. I also noticed to day that my volts gauge dropped to around 12v when I was driving and the cel came on shortly after. Somehow my voltage drop is affecting my fuel pump performance. The voltage drop is completely random from rpm/speed/or what electronics are on. Sometimes it will be just over 14 and other times it drops to around 12. It doesn't jump around and it usually stays at that reading for a while. Anybody have any ideas? Alternator? short circuit? Thanks