I just recently did an MPFI swap on a 90 CRX DX, after the swap and all the wiring was complete I started up the car, it idles perfect no misses or anything but once you hit the throttle even a hair the car totally bogs out then backfires. I checked the crank wires and switched them both ways and it does it either way. If anyone has had this problem before it would be greatly appreciated if you could help. I was thinking maybe the TPS but not too sure. I have done about 6 or 7 MPFI conversions and none of them ever did this so I am a bit stumped. TIA

 

I have the same problem with my 89 hatch, but I didn't do the swap, so I don't know what would be wrong. It runs fine most of the time, but every once in a while it runs like what everyone says is ignitor failure. I have no clue. I tore apart the dizzy, everything was fine, put it back together and it runs fine now. My idiot light is still on though. Mine also seems to take a while to warm up... It won't run right with the choke going, but usually all it takes is a good 3 grand rev and just let it idle for a couple minutes. I would figure your problem would be fuel pressure. Either regulator or pump. It may be your TPS, not too sure about it though, never had to deal with 'em... Just check your whole fuel line. Wait, did you swap the whole MPFI engine, or just did a conversion? If just the conversion then it wouldn't be fuel.

 

did you switch the 2 outer wires on the TPS? if not, then try doing that first

 

Yea the motor had the same problem in a different car. I used the same wire harness though and I am guessing that maybe the harness is fucked in one way or another. Thanks for the advice though. yes the TPS wires are switched..

 

I just did a d15 swap and mine did the same thing. So I put a new motor in and it still did it.
So then I was like what the hell, I found out that it was a plugged cat! LOL
I took the lower factory header off ran great so I gutted it .
Dont know if that is your problem but You never know.