Lean Problem

[Stern90LX]

If you're still running 19lbs injectors with a blower on there that's your problem. Way under sized for what you're doing. They just can't provide the amount of fuel per cycle that is needed in a boosted application. Even 24# injectors only support up to 300hp nominally(80% duty cycle) at the flywheel.

[ThePunisher95]

No I have 28lb injectors from a LS1

[ThePunisher95]

Yeah but at Idle even 19 lb injectors would be enough just to idle. I cant idle rich just lean

[ThePunisher95]

So I dont know wtf to do now. Change MAF(free), fuel filter good fuel pressure, no leaking fpr. Tired of this car already.

[fazm]

So I dont know wtf to do now. Change MAF(free), fuel filter good fuel pressure, no leaking fpr. Tired of this car already.

have you checked the obvious like vacuum leaks, intake leaks, etc?

[ThePunisher95]

Yes sir. Gonna change the fuel pressure regulater tomorrow hopefully and re check for vacuum leaks again while Im at it.

[swirl]

Ok lemme get this straight ur running a stock maf meter with larger injectors?...thats a major problem there. second u need a fmu when running a supercharger to give it more fuel under boost. lemme know if u need help i know a lot about tuning and these cars.

[ThePunisher95]

Ok lemme get this straight ur running a stock maf meter with larger injectors?...thats a major problem there. second u need a fmu when running a supercharger to give it more fuel under boost. lemme know if u need help i know a lot about tuning and these cars.

Stock MAf and bigger injectors would cause a rich condition. Right?


And I havent even boosted on this engine yet. I havent punched cuz I dont need to go into boost to start going lean.

And as soon as I get the Tweecer ill add more fuel. I want to be some were in the low 11's air/fuel to be safe and not to much timing.

[swirl]

technically yes is should richen the car but u dont know the inpedence of those injectors weather its high or low impedence makes a huge diff. Mustangs normally run in the 17ish af at idle but at 2k that isnt normal. The computer may be seeing it getting too much fuel because of the larger injectors and slowing the pulse rate to almost nothing causing it to go lean. You HAVE to fix what u know is wrong and those injectors are wrong. Id put the 19lb injectors back in just to see if that helps it wont hurt