Need Help With Rpm Problem

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zc_hatch

Senior Member
i did a zc swap in a 91 civic hatch dx, but before i did, i bought the car buy paying off a mechanics lean. and it had a busted head, we replced the head, the car ran rich til about 4k rpms then dumped off to lean, but the engine locked up before we could figure it out, then entered the zc, we got it all in and the zc does the same thing, runs rich then lean and loses pwer about 4k rpms, we thought maybe it was fuel delivery, so we replaced the filter, lines, pump, its fine, then maybe clogged exhaust so we gutted the catylitic and then replaced the muffler with an arospeed p.o.s. just to see if that worked, didnt help, we have adjusted the throttle body ever which way and cant get it, so the only thing left on the car that hasnt been changed is the map sensor, but i got another mechanics opinion on the map sensor and he said it wouldnt run at all if it was bad, but i think it could run, so before i go and buy a map sensor i wanted some second opinions or to know if anyone else has had this problem, remember both engines did the same thing with the firs was a d15 and now its a zc the d15 had a pm5 ecu, my zc has a pm6 so i know its not the ecus cuz they were changed also.
any ideas
jones
 
did u reverse the two wires on the TPS sensor becaseu the SI ecu turn the oposite way then the DX another thing is check ur spark plugs/plug wires and all the wires that were used when the wiring was done if u have a short it will go into effect right arount 4k where alot of load is put on the electrical system of the motor..anothere thing ur ECU might be faulty or there is a fault in the electrical system of the car (thats why it blew the first motor) so check all of these things out and chec the dist. and stuff like that and i bet u will find the error...
 
wrong wrong wrong, the old engine had a diferent ecu, it blew because the oil pump went bad when the previous owner ran it low on oil, its not the p;ugs or distributor because those are all new and none of the wiring is messed up because i used a hasport harness, its something that was on the car, im 140% sure its the map sensor, its the only thing left on the car besides the tranny and the tranny dont control the rpms by vacuum. ive had 3 diferent ecus with this engine, 91 civic si, stock integra ecu, and now i have a remapped integra ecu and they dont make a diference. thanks for trying to help, but im just buying a map sensor tomorrow, already spent over 4k on this damn old honda so whats a little bit more moola
lata
jones
 
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