something went very wrong

i have been driving my truck since i finished it Monday. it was doing okay, even though it isn't tuned for the cam yet. i found out the smoke it was blowing was because our dumbasses forgot to put in the dipstick. put that in and it stopped smoking. but i noticed that i was running kinda rich in higher rpm's and i have the FMU so i decided to lean it out a tiny bit. and then all hell broke loose. it started sputtering under part throttle. and so i pulled back over and tried to get it back where it was but never could. nothing i tried made it better. then all of a sudden it wont hardly stay running and its going dead lean, or like 19 to 1 a/f's. so i limped home and pulled it in the garage. its sucks because it was driving fine besides not having nearly the power i was hoping for. and shifting at 5k unless i manually hold it longer. i have a tune coming sometime soon and maybe that will help. if it doesn't i'm going to a local dyno to get it tuned. i am still on stock injectors, but they have been holding up, do you think they could have just wet the bed. my brother in law is going to 60's in his stang and said he would actually GIVE me his 42's. that will rock. if my truck is okay. it will still idle fine. just if i try touching the gas it sputters and wants to die.

Time for a compression test.

I can't believe you stuck with the FMU & stock injectors. Those things are junk.

I bet you're losing fuel pressure somewhere. I've ruptured the fuel hose betweeen the fuel pump and the tank assembly. That will cause you to lose performance and run lean.

it was a intercooler hose that popped loose after the maf. i don't understand why it read lean, but everything is fine now. should i take the fmu off or leave it on, because i have a in line boost pump, will it overflow the stock fuel pressure regulator?

Sounds like its all in the tune and fuel delivery. You have the correct fuel pump (a 255l/ph I assume), so that is out of the question. I would DEFINITELY put in bigger injector and tell Allen to tune the new PCM for the 42s... Get those 2 things done and i guarantee you that it will run the way it should. You have done enough of the bigger mods to not allow for the current PCM to run the motor correctly. I would park it like you said and wait for the new tune and bigger injectors...

well, its my work truck, and i put the 22's back on the suburban so i don't want to use that anymore. so i richened up the lower rpm's to like 10.5, and at redline i'm at 12.5. but i never take it there until i get my new tune hopefully in a day or two.