Rich Conditions

[Joe Muckle]

I have a 2012 5.3 Vortec Silverado 1500, I keep getting rich left and right bank codes, the truck starts very hard cold. When it does start it is very loaded up with fuel. I cleaned the oxygen sensor and also checked fuel pressure, it has 57 psi with the key on and drops to 42 psi when running. Looking for some input to fix it, I’ve been a heavy equipment mechanic for 40+ years but don’t work on any of the newer fuel systems.

[davester]

42 psi when running is too low.  most likely you need a new fuel pump.

[CamGTP]

36 minutes ago, davester said:

42 psi when running is too low.  most likely you need a new fuel pump.

It's not too low. These trucks have a fuel pump control module that will vary the pressure from 40-60psi on demand.

 

If you have a scan tool check to see what the alcohol content percent is reading. If the reading is way high then it needs to be reset. I've seen trucks get stuck at 50-70% for some odd reason even though the person is running regular E10 fuel.