Ok first off I have a 2006 lsj with 86xxx, gm stage 2, cai, zzp midlength headers/catted dp, and megan racing catback.

The problem originally started with my car throwing the p0171 code and being super jerky through 1st and second. My ltft's were ridiculously high because of this so after lots of searching on here I have checked for vacuum leaks and replaced any lines that needed, cleaned the maf, changed the air filter, new fuel filter, changed plugs, tested evap solenoid.

Now after all that my car is no longer throwing any codes but I am still running extremely rich. The thing is my ltfts stay somewhere between -2 and 7 when I am on the gas but the second I start to lift up at all it will max out. I am still getting pretty bad mileage because of this as well as an obnoxious amount of afterfire. Any ideas on what it could be because I am at a loss?

 

Injector? Anyway you can smoke test it, that'll find the leak.

 

Thats what I was starting to think. Ran out of time to test them today but I should get to that tomorrow.

 

Ok so I tested to injectors to see if any were leaking and they aren't. Could a clogged injector cause the same problem? Is there any way for me to test for that myself? I have run a couple bottles of injector cleaner through it in the past and it seemed to get a little better but still not where it should be. I also went ahead and replaced about every vacuum line. Is it possible that this is all because of the tune the car has? I haven't had it tuned myself and the previous owner said it was custom tuned but for all I know he could just be talking about the gm stage 2 tune.