P0300 misfire ccde

[schwaz]

I have a 03 1500 Z71 with 42K on it. Engine light came on and codes read P0300 "Random/Multiple Cylinder Misfire Detected" and P0101 "Mass or Volume Air Flow Circuit Range/Performance Problem "

 

The truck sounds like a beast. no power expecially uphill. ran it up to Murrays to read the codes again after the fixes below and barely got to 25 mph coming home.

 

i changed the spark plugs and wires, two of the ceramic heads were cracked. Changed the fuel filter, sprayed the MAF sensors with electronic contact cleaner.

replaced the K&N filter with a regular FRAM.

 

replaced the PCV valve, there was no rattle and the valve was empty. any chance the ball bearing got pulled out. There is vacuum in the hose, though.

 

the fuel pressure tops at 54 with the engine off and 48 when running. fuel pump?

 

The Evap purge behind the throttle body seems loose.

 

Any way to clean the injectors without pulling them out?

 

Any thoughts or tips would be appreciated. I love this truck and dread the dealership.

[citydriver]

Welcome to the board

I know that you DREAD the dealership....most do...but w/only 42K on the odometer,the fuel/emmisions system is still covered under the Federal Emissions Warranty It might be worth your time to have them check it out...

Just A Thought...............Good Luck