Need Help!

[amandar]

okay so my brother has a 96 GT. We have been chasing a problem for awhile. We are getting codes for bank1 & bank2 too lean, which the actron says common fixes are fuel pump (replaced with accel 500), intake manifold gasket (replaced). We are currently at a Loss, I'm attaching the datastrem from the OBD reader.
This car does have a BBK X-pipe, but had MIL eliminators put on. The car currently has the stock intake as the CAI made the issue worse. There does not seem to be a air leak as we check all over and can't find one? Someone please help us out we are done throwin parts at this car.

Replaced parts:
MAF
IAC
TPS
EGR
PCV VALVE AND HOSE
ALL NEW VACUUM LINES
INTAKE MANIFOLD (cleaned injectors and fuel rail)
02 UP AND DOWN STREAM
NEW MIL ELIMINATORS
FUEL PUMP (accel 500,high perf pump)
ALL NEW SPARK PLUG
CLEANED THROTTLE BODY

 

[amandar]

Second image of datastream

 

[MustangIIMatt]

Your long-term fuel trim is WAY off. (Which probably means this has been an ongoing problem that's built up over time.)

A few things to look for:

1. Are there any exhaust leaks, especially ahead of the upstream O2 sensors? If so, it will screw with the readings, and make the ECM think you're running lean while actually causing you to run rich.
2. Take a can of carburetor cleaner or non-chlorinated brake parts cleaner with the straw. With the engine running, spray it anywhere on the intake manifold where it meets another part (throttle body gasket, where the intake manifold meets the heads, etc.) If the car revs up suddenly while spraying, you've found your leak.
3. What is your fuel pressure at? (should be roughly 40psi at idle, I don't have access to Mitchell here at the house, so I can't get you the exact spec.) You've replaced the fuel pump, but even the best fuel pump can't do it's job if it's regulator is bleeding off pressure. To check your fuel pressure, you'll need a fuel pressure gauge rated for fuel injection, and the know-how to use it. If your fuel pressure is low, remove the fuel filter and attempt to blow through it (I prefer to use a piece of clean hose rather than putting my mouth directly on the filter, hate the taste of gasoline) if you can't blow through it, your fuel pump is going to be having a hell of a time pushing fuel through it. If the filter flows pretty easily, and you don't see all kinds of crap built up in it, you can reuse it, but I tend to replace them with a new one anyway when I have them out, they're cheap and relatively easy to do. If the filter isn't restricted, it's time to check the fuel pressure regulator.

Check those before throwing any more parts at it.