Having a bit of difficulty here.

Just installed ZZP Phenolic spacer, ZZP Stage 3 LSJ heat Exchanger, ZZP Dual pass endplate and ZZP option b.

I have a 2007 Cobalt SS/SC with stage 2 as the only engine mod. Now I HAD a injen
intake which I bought new on the car but it threw P0171 so i changed it back to stock and haven't had a problem with the light going on although it might still have been there???


Upon completion of the recent installations(ZZP parts mentioned above) I am now getting the P0171 and P2261. It was running at about 1200rpm but I have since corrected that and it idles fine between 900 and 1000rpm


After reading multiple threads I have done the following

First I kept clearing the codes about 3 times

Started out with P0171,P0300,P2261

Cleared the codes

found leaks at injectors

installed new insolators on the injectors first THEN put in holes instead of putting the insolators in the head first and sliding the injectors into them

no further leaks at injectors

zipped tied pcv valve hose to intake very securely I beleive this was my idle problem mixed with the injectors leaking



Sprayed carb cleaner on all hose joints around intake manifold and supercharger around throttle body and around the seems in the intake tubes. No change in idle

Taken the intake apart several times to check for holes and leaks

Cleared the codes with the interceptor

P0171 comes back, light on

cleared the code with the interceptor

P0171 comes back, no light.

I have no way of checking for fuel pressure but could this be the fuel pump?

I check my STFT and it is about 4-6 and my LTFT stays at 19.1

any help or suggections would be helpful

At this time I'm thinking it has nothing to do with what I did but has been there all along ever since I took my intake off but that is just s theory at this time.

Joel

 

did you put the 3 spacers on the ic pump bracket that come with the phenolic spacer?

 

Yes i did put the three spacers behind the ic pump bracket.

I also just check my oil dipstick tube it is in all the way and my oil fill cap in on and tight.

where are the LTFT supposed to be cause I read somewhere they are supposed to be close to 0 and mine are at 19.1 at idle??

 

any suggestions? I'm taking it in to a trusted mechanic tomorrow...............I even disconnected the bypass valve, what I got there was well more boost!!! haha I'll have to keep that in the back pocket till i get things running right.

 

LTFT = Long Term Fuel Trim,

Ideal it's suposed to be 0.0 all the time. That is with a PERFECT tune...

The fuel trims to the best of my understanding let the PCM add fuel to the tuen (Fuel Trim postive) if its too lean, or subtract fuel from the tune (Fuel Trim Negitive) if its too rich. It's allowed to go to up to about 20, or down to -20 or so. If your getting like 19.1, then something is wrong. It means that the PCM is trying to add more fuel then what it's programed for.


This is consistant with a vacume/intake leak,

Did you check the seal between the Supercharger and the Intake manifold? It should have a metal gasket with a rubber trim arround the inside. Also there is another small gasket for the supercharger bypass where that connects to the endplate. Also check your throttle body to Supercharge seal.

Did you use both intake manifold gaskets? One on each side of the spacer? It sounds like you did since you said you dont have a leak there. Let me know if/where you find an intake leak, because I have that same spacer, and sometimes if im going downhill slightly and push gently on the gas my trims trip the P0171 code also. You can get a fuel pressure tester and check it under the hood, just hook it up and turn the key to on and it should go up to like 50 or so when you hear the pump go on. Did you check for aleak on that plastic tube that hooks up to the throttle body? I remember after installing the sparer mine seems kinda streatched.
Good Luck

 

I checked between the supercharger and the IM. I did install a new Supercharger to IM gasket and I installed a new endplate to IM gasket.

I installed 3 pieces between the IM and the head the gasket, spacer and gasket as well as no leak at the endplate to Supercharger. Yes the throttle body tube it leak free as well and I did notice it was streatched too because of the spacer.

I've seen guys cut it and add in a small section of hose I just don't have that size to do the trick but no leaks.
Throttle body to supercharger seal is good.

Its gotta be something small due to the nature of the code.

hmm

 

You've got a post maf air leak somewhere... did you have the maf out? maybe you got it dirty.

 

Turns out it was the 02 sensor!!

Thanks for the help everyone.