88 2.9 running like crap!
I have an 88 2.9 5 speed 4x4 180k that won't run right. The down and dirty is this - I've tried everything that I can think of so I need some suggestions.
The truck has fuel pressure (30-40 constant) and will start but runs at ~500rpm, wants to die and you can't rev it - like it's starving for fuel. If you play with the throttle for a while it will kick open and run at wide open throttle but within 10 seconds will drop down to 500 rpm again even with the accelerator mashed to the floor.
Things done so far:
New fuel with stabilizer and amsoil additive for any old fuel plus injector cleaner
The truck now reads code 11 - system ok
replaced map/maf sensor
replaced TPS sensor
replaced Fuel pressure regulator (reads 30-40 psi)
replaced IAC sensor and motor
replaced fuel filter
replaced distributor cap, wires, and plugs
I've tried to check for vacuum leaks and sprayed carb/injector cleaner all over to see if the idle would pick up due to leak - nothing
I've thought of the coil (has aftermarket autometer on it), cat (but the idle surges up and down), injectors (but why does it all of a sudden go to wide open throttle if they were clogged?)
I'm tired of throwing parts and money at this thing, any suggestions other than insuring at full coverage and setting it on fire?
I've searched this and several other forums and there is no firm answer to my issue