I wanted to see what everyone else here thought, I have had a P0171 for some time now and have checked/replaced a few things along the way just want to see if anyone else has any suggestions or if i should be looking at doing some tuning? my LTFT were 10%+, reset my fuel trims now at 0 but STFT are at 15-20%... have a feeling the LTFT's will go back up with more driving.. onlything i can think to check again is the Fuel pressure.

Here is what i have done so far:
* Replaced vac harness on the top of the TB/Charger
* New front manifold gasket and DP gasket (when installing Plog/DP) no leaks
* New Acdelco O2 sensor
* New fuel filter
* ZZP mail order tune and stock tune
* Smoked engine found 1 leak, repaired
* Brake clean for leaks in vac lines/intake gaskets (none found)
* Cleaned stock MAF and replaced with Cardone MAF
* BG Fuel injection system Flush to Fuel rail (does feel like it is smoother.. maybe just in my head)

Mods:
ZZP 3" Catted DP
ZZP P-log
ZZP Mail order tune
3.4" or 3.25" MPS
3.5" FWI (still have MAF screen)

Kinda starting to think it needs to be tuned to get 0'ed out.

S

_________________
Shane "RedZMonte"
2004 Z16 Z06: Virgin
2000 SSEi: Kenwood DDX512, 3.25" MPS, ZZP DP, PLog, Puck Mount, NGK TR7's, DHP Tuned
1995 Monte Z34: T04e "60" turbo, 42.5# injectors, Borla Catback, OBDII swap, DHP Tuned, Much more...

Have you checked for leaks around the EGR pipe?

_________________
*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

I have smoked the engine and soaked everything including the egr and lim where the egr meet and have not seen a change in idle or any smoke leaking. I have been reading it is a common issue so I double checked it and cannot find a leak... Any other ways to check it, I would be happy to try.

_________________
Shane "RedZMonte"
2004 Z16 Z06: Virgin
2000 SSEi: Kenwood DDX512, 3.25" MPS, ZZP DP, PLog, Puck Mount, NGK TR7's, DHP Tuned
1995 Monte Z34: T04e "60" turbo, 42.5# injectors, Borla Catback, OBDII swap, DHP Tuned, Much more...

Some have reported finding cracks by removing it and giving it a visual inspection under a bright light. Others have plugged one end and filled it with water.

_________________
*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

going to test fuel pump tomorrow... it has been acting odd... feels like the engine is choking then livens back up like it starving for fuel.. question is if i need a pump the racetronix seems to be a drop in same as a W-body... Do i need the wiring harness kit? i have had Walbro pumps in the past in my Monte and the stock harness plugged right in but it sounds like thats not the case here.... Anyone have experience with this pump?

http://prjperformance.com/Products/Ract ... index.html

_________________
Shane "RedZMonte"
2004 Z16 Z06: Virgin
2000 SSEi: Kenwood DDX512, 3.25" MPS, ZZP DP, PLog, Puck Mount, NGK TR7's, DHP Tuned
1995 Monte Z34: T04e "60" turbo, 42.5# injectors, Borla Catback, OBDII swap, DHP Tuned, Much more...

Fuel filter?

Never mind lol.

_________________

lol i do that quite a bit...

I thought about replacing it again to make sure there isnt some *shoot* clogged up in it that made it past the pump... never know right..

_________________
Shane "RedZMonte"
2004 Z16 Z06: Virgin
2000 SSEi: Kenwood DDX512, 3.25" MPS, ZZP DP, PLog, Puck Mount, NGK TR7's, DHP Tuned
1995 Monte Z34: T04e "60" turbo, 42.5# injectors, Borla Catback, OBDII swap, DHP Tuned, Much more...