1994xj

I have a 94 4.0l aw4 165k on the ticker. Cat is gone. My problem is that it has a slow take off sometimes, like it has no fuel, and backfires under load ( and under no load at times) when first applying throttle. This is an intermittent issue. Sometimes it takes off just fine. A constant issue i am having is that the engine will NOT go over 3500 RPMs load/no load. I already have a bunch of new parts on this thing. It has done this 2nd issue since the day i bought it. Firing Order and Timing is correct ( checked today when i got home).

New parts
Plugs/ wires
Cap/Rotor/Coil
Distributor pickup
TPS
Crank Sensor
Fuel Filter
Fuel Pump
Injectors
MAP Sensor
02 Sensor
Head Gasket
Exhaust Manifold
and Full exhaust

I have no idea where to go with this issue I can make a video of this from inside the cab if neccesary.
Any and all help or suggestions will definitely be appreciated!

1994xj

bump

Roler

CPS: what brand did you put in? OEM is recommended (but more difficult to get)
TPS: have you tested it to check for 'gaps'? Analogue meter is best for this
Have you done a fuel pressure test?
What injectors did you put in?

1994xj

CPS- BWD Brand from Oreillys.
TPS- Not tested yet but i can do that.
Have not done fuel pressure but i can take the hose off the regulator and it doenst improve anythng.
Injectors are rebuilt 19lb orange ford 5.0 injectors