Please help

[kimcrwbr1]

Maybe the computer is getting mixed signals unplug the two egr solenoids to take them out of the loop the two pins on the computer are for the 2.3 with the egr maybe it is looking for a response when it senses the solenoids are connected. I dont have the schematic for the 90 2.9 but the 3.0 has the distributor the 2.3 and 4.0 are distributorless I can only assume the 2.9 and 3.0 would be the same.

 

[kimcrwbr1]

Pin 52 on the 87 is for the egr and on the 89 it is for the shift 3-4 solenoid and looking closer the 90 3.0 has the MAF sensor also, does your 2.9 have a mass air flow sensor not plugged in that could explain everything with that computer not getting the input it needs.

 

[--weezl--]

1990 could have a 2.9L for 2 reasons, 1) it was an early 1990, marketed as a 1990 but it was actual an 89, 2) there have been situations that things exist that aren't supposed to, i had an 88 bII with a 2.3L v6, yes, a 2.3L v6, that motor isn't supposed to exist in north america period, but yet, i had one with that motor, looked just like the 2.9L but shorter by atleast 6"... sat really low in the engine compartment...

the knock sensor, if present, and if the computer is looking for it, but not getting a signal from could cause your problem, if the computer is interpreting the "signal" or lack there of, as a ping, it could continuously retard the timing to the point that the motor barely runs, or stalls out completely... your spark would be just way too retarded...

drilling holes in your exhaust before the o2 will never help your situation, why, might i ask, did you drill them? i would plug them, reset all codes (which you should pull anyways) and see how it runs

 

[kimcrwbr1]

Look in the tech library under maf conversion with a 1990 computer you can add a maf sensor without changing the harness and forget about the egr you already have the vehicle speed sensor needed.