losing my mind help

supraflydaddy45

New Member
Sep 20, 2012
3
0
0
stockbridge Ga
I have a 87 7me an I have jus installed another motor in it. It runs great as lomg as it idile but once you hit the gas it revs then drops off then revs then drops off. I have checked rotor, cap, fuel pump, fuel filter, plugs, wires, timing, but all to no avile. It use to start with the key but now there is no power from the key to the start so i an havin to us a jumper wire to start the car but once runnin it idl fine but still can't get car to drive without the crazy surge thing goin on . PLEASE help!!!
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
You didn't say what rpms it revs to or whether it does that even with the pedal held to the floor but try this: with the engine off enter diag mode and with the tranny in Park (if an auto) and AC off press the accelerator. Get a 51? If not there's your answer. Another way is to simply unplug the TPS and see if the surging disappears. If it does your problem won't be hard to resolve.
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Well, it sounds like fuel cut. It's caused by the IDL contact remaining closed while airflow and rpm increase. The ECU doesn't approve of this illogical situation and shuts injection off until rpm falls to a safer level. Try the tests I said to confirm.