ok here's the deal. I have a ls turbo with 450 injectors, chrome programed ecu, lightweight flywheel, stage 2 exedy clutch, dual valve springs, new fuel pump, new fuel filter. leaning out really bad at 3500 rpm's. when on the dyno even my tuner can't figure out why. checked map sensor and anything else we could think of. even with fuel cut up to 60% duty cycle it still leaning out. on all motor it still leans out. I really need help. if you have any ideas please let me know.

 

try the turbo forum

 

do u have a way to check the voltage to the fuel pump during a run, also monitor the fuel pressure too

 

What tells you it's leaning out exactly? Your tuner, or are you guessing because of how it runs, have you adjusted your spark plug gap at all after adding any of the turbo,injectors, fuel pump, etc... I know with my 3000gt, spark gap was a huge deal on how it ran because of injectors and the twin-turbos.

 

tried new plugs. ngk bkr7e's. and in response to the leaning out question. tuner tells me when to shut down because of the leaning issue.

 

"All motor" isnt going to help if your fuel map is off across the entire 3500rpm section. I'd suggest adding more fuel....and if that doesnt work, add even more. Ofcourse it could be the fact that you're running DSM injectors (probably from a 90 model) and they're just flat worn out.

 

tuner tried additional fuel more and more and more. just plain not enough getting to em for some unknown reason

 

Does the AFR come back into rich after 3500?

 

no. won't go any further than that. be scared to if it did.

 

Then something is very wrong. If your car won't go rich under a no boost situation at only 3500 rpm's then you have some fuel issues somewhere. Have the injectors tested and check your fuel pressure and pump output

 

sounds like injectors to me... yep need to check fuel pressure!

 

ok update time. hopefully this will help somebody out there. problem solved. the bottom of the intake manifold gasket was blown out in several small spots. not enough to hiss loud enough to hear it. but bad enough to cause this.

 

it took a month to realize that? lol. i'm just picking.

 

my thoughts exactly. lmao pissed me off