I’ve got a freshly chipped/tuned p28 (that was benchtested after the tune) in my H22a 5th gen with a jumper harness, ‘95 lude injectors, resistor box (p28 tuned for these injectors) and an obd1 dizzy. The EGR, secondary O2, IABs, EVAP and knock sensor are tuned out/not on the p28. I should also add that I had this same setup (minus the injectors, resistor box and p28) running my stock 5th gen ECU with stock obd2 injectors for a couple years up until the point I started the p28 swap so I know everything else should be good

The Problem:
When i start it, it’ll want to die after 5-10 seconds unless I give it like 1/16th, 1/8th throttle and keep it running for a minute or two then it’ll idle on its own. If I give it any more throttle though, it’ll want to die, like it’s getting too much fuel or something. I CAN get it to rev up to my 2-step point (4500rpm) but I can’t just floor it to get up there.. I have to modulate the throttle kind of gently and it’ll hit a bit of a wall around 2000rpm. I’ve taken it for a drive and under moderate/heavy throttle it won’t want to accelerate and it’ll stutter and jerk a bit. Now I’m getting a code 16 (injector code) and code 1 (O2) Any insight would be amazing, I’m kind of at a loss and grasping at straws

what I’ve done so far:
Checked fuel pressure and injector circuit wiring. changed my FPR and fuel filter. Swapped out the MAF for good measure. Fuel pressure is around 40ish and goes up to around 50 WOT. I’m getting about 8.8-9ohms across each injector circuit from right before the resistor box to the ECU injector pins when the car is off (each injector reads 2.4ohms, each resistor box pin reads 6.1ohms) It still hesitates and stutters under load.

 

If the car with the engine combination that you have now has not been on a dyno... it hasn't been TUNED. What you have on your "chipped" ECU is a BASEMAP... it might run the engine OK... or it might not.

 

well sorry my grammar isn’t correct but the fact remains, I need help.. he said he’s used this same map before for someone else’s setup which was the same as mine and they had no issues so I still need help troubleshooting

 

JR already said it. You need a tune. A wideband will tell you the whole story.

99.9% of the time with issues like this on an untuned vehicle the ECU calibration is at fault. Just because "it worked on someone else's car" means nothing. Even if vehicles are "identical" they will run differently on the same map. There are so many other variables like carbon build up, actual injector flow, how strong the charging system is, etc that will change how they run.

I would not recommend driving it until it's tuned because it's very possible for you to do actual physical damage to the engine. Either detonation from lean conditions or washing out the rings/diluting the oil from overly rich conditions.