My check engine light keeps turning on the same code p0442. I had the evap pump replaced about 3 months ago and it was fine then one day it clicked on. I put a new air intake kit on about 1 month ago but i dont think that has anything to do with it. The funny thing is one day it was on and rev my engine to 6000 rpms and the light clicked off and i thought i was fine then two days later it clicked back on. what could it be?

Thanks Ryan
P.S. I dont know very much about my truck and I do have a Haynes book

 

Evaporative Emission System Leak Detected (small leak) P0442

If not the gas cap being loose or leaking, somewhere you have a leak and that is probably going to be a PITA to find.

 

mine came on after the body lift because the gas filler hose.. the hose going from the cap to the top of the tank.. was loose.. just that hose and also the gas vent hose... if not check all the lines running from the evap canister on the passenger side frame rail (looks like a big black coffee can)

 

start with the gas cap, its easy, cheep and dont forget to reset the comp. (battery disconnect for 30 seconds to a minute usually works good, longer to be sure)