Thread: swapped motors wont rev past 2500rpm

ive got a 93 G20 put a jdm motor in it and the car had emissions on it but the new motor does not i hooked everything up and it wont rev past 2500rpm like its the rev limiter i read that if u unhook the battery it would reset the ecu didnt do anything then i read it could be the mass air flow sensor but the car ran fine with the old motor but ive double checkd everything and dont know what it is and the check engine light isnt on so i dont think i miss anything but i got to get it figured out

Won't rev past 2500rpm usually indicates a problem with the maf or maf wiring. Try unplugging the maf (disconnect battery when inserting/disconnecting the maf) and start the car, if no change then your maf is bad. When you insert the maf plug make sure it goes in all the way, and give the wires a little push into the plug. Or, there could be a problem with the wiring itself.

k thanks a lot

is there anyway to clean a maf??

... ground wires of the maf.. did you put those back on?

will i by passd it by hooking the to positives together n it runs like its suppose to but now its a little rough but is that just because theres no maf?

Bypassed the maf? Be careful with that. Don't want to fry your ecu.