P0101 and 3 more codes

Hello-- I've got a 2005 Chevy 3500 dually chassis cab 4x4 auto 6.0L.

Last week it started running very rough. Threw codes p0101, p0134, p0171, and p0300. After reading about these notorious intake gasket problems, I just went ahead and replaced the gaskets. The old ones "looked okay", but I just shrugged it off and went along with the $75 replacement Felpro Premium gaskets. 1 week later, the same thing is happening and it may even be just a little worse than before. I checked the torque of the gaskets and it's spot on. However the fuel pressure is in the 45's while idling.. Spikes up to about 55 WOT, and that is about all of the diagnostic info I have.:runaround:

Any ideas? Thanks for looking.
--Ken

^bump^

Anyone? Is it possible that the intake has a crack in it? I've never dealt with this plastic stuff before.

101 is a mass air flow issue or as you said a vacuum leak or any air entering behind the maf, also check on that fp seems low.

Hello-- I've got a 2005 Chevy 3500 dually chassis cab 4x4 auto 6.0L.

However the fuel pressure is in the 45's while idling.. Spikes up to about 55 WOT, and that is about all of the diagnostic info I have.:runaround:

Any ideas? Thanks for looking.
--Ken


fuel pressure is too low 53psi is the lowest ...

the forum has here a fuel testing proceedure ..follow the proceedure and this will give you what componet is defective ..usually the fuel pump...

keep fuel level above 1/4tank,use delphi fuel pump,replace fuel pump relay if the pump is defective ..

replace fuel filter every 30,ooomi...

Alright I'll look closer at the FP, and I'll search for the test procedure. Thanks!