Im still having issues plz help

[02_lightning_NP]

Ok about a month ago i ripped my heaton of ande tossed on a brand new MP sc. sinc then i keep throwing two codes. p171 p174 i know what these two codes mean and Ive down everything to try and find the leak i bought all new gasket for the TB and plenum i even sealed the Sc with a little bit of extra sealer. I've checked all the hoses and none are missing or cracked. I checked my air fuel ratio and with the truck idling and cruising normally im right aroun 14.4 and when i jump on it she sits around 11.7 and holds steady till i lift of and cruise to a stop when it jumps really high to like 20.0. But i dont hear any backfiring jsut to let you know. and if i put my foot back into it it goes right back to where it should be. I replaced alot of the little vacuum lines thinking maybe a tiny hole or crack and still nothing. Everytime i replace something i clear the code and drive and 35- 40 miles down the road the codes come back. I'm totally lost and have no clue where to go now. And i cant afford to toss her into an expensive shop up here where itll cost me a couple grand to fix something minor. any ideas guys.

 

[operator1391]

I had the exact problem, lean on bank 1 and 2. I also checked all my vacume hoses and nothing, My problem was the 90 on the lower intake manifold, the 90 tends to go bad, I had to remove my s.c to get to it.just follow the pcv line that goes behind the s/c and down to the lower intake manifold

 

[02_lightning_NP]

already checked it and it looked fine.

 

[Dr. Matt]

I wonder if it could be in the tune. if you are looking good like that on AFR when driving it is OK to go lean off the gauge when coasting. What has your tuner said? What injectors do you have?

 

[jmorando05]

Either tune or smoke test..

 

[02_lightning_NP]

im still running my factory injectors cause i had a couple leaking 60 #ers. and i do all the tuning myself with sniper software. i've changed the tune to see if that was it a couple weeks ago and the light still comes on. i have no clue, i'm gonna chage out my fuel filter and air filter this weekend and see if that helps. i just hoestly have no clue and im tired or throwing money at it trying to fix stuff and none of it works. know what i mean...whats a smoke test?

 

[02_lightning_NP]

so ya heres anther riddle for ya, i went to the drags this last weekend and everytime i went WOT i'd hit 10#s of boost sometimes 12#s and i'd fall off to nothing after that....
i should be getting 16 to 17 #s at full throttle with a 6lb lower and a 2.7 upper but im not and i checked the boost guage hoses and they are all new and even installed an aftermarket gauge and it says the same thing. what could cause that along with the two codes p0171 p0174. i changed the fuel filter and checked for leaks and nothing. im lost. again

 

[Adam99SVT]

Would it be a safty shut off, I know that when some code go off it will dump the boost....if you even have that option on an mp blower.

 

[Dr. Matt]

Sounds like exactly what Adam said. Your boost bypass valve is open and dumping boost. Even with a little belt slip you wouldn't drop that far. I don't know what those codes are off the top of my head but I'm sure someone else will chime in.

 

[heetstroke]

You and me both brother. I replaced all vac lines,o2's,cleaned all sensors,everything. At least your not getting detonation like me. We are about to pull the whipple and manifold off and redo the gaskets along with a few other things. I hope we both get are gremlins fixed so we can run what are trucks are supposed to in June. The codes is a Lean code for bank 1 and 2. Check for exhaust leaks around your headers/mids and check your o2 extensions out one may of melted a little due to heat from the header
Ford DTC Codes

 

[02_lightning_NP]

damn i didnt even think about those little wires. i'm gonna rip into it tonight and see what i can find. i'm gonna check the 90 hose one more time as make sure its not it. The boost bypass valve is the little butterfly in the back with the vacuum operated valve sticking out on the drivers side right? damn gremlins. now that i think about it i need to tcheck my egr valve. thepipe was loose last time i checked it and when i tightened it i ran about 200 miles before the damn code threw again. maybe it just wont stay tight now and keeps working its way loose. i'll let you guys now something later...dr. matt i need your number bro...a couple friends and i are planning on heading down to palmer soon and i wanted to link up with you when i am down there.

 

[Cialis]

If you have an oil seperator, remove it and then test. I was having the same issue and couldnt find any leaks. Just on a chance, I pulled the oil seperator off and never threw the code again.

 

[02_lightning_NP]

i thought about that and took it off and ran it for a little while and no it strill came on...