Need help I have a 08 Chevy 2500 hd with engine code p0174 wanting to no what could be wrong

 

A P0174 is for fuel trim system lean bank 2. Could possibly be a vacuum leak between the master cylinder & brake booster. But more than likely the catalytic converter or O2 sensor are having issues. Hard to tell without seeing what the long term fuel trim readings are. You could also have a dirty air filter, bad MAP sensor, dirty throttle body. The list can go on & on.Best bet is a scan tool so you can see what the sensors are reading or you'll just be throwing parts at it hoping you guess right.

 

Need help cleaned throttle body on truck now idling high how do you reset idle