96 corolla misfiring
veedubmechanic
12-08-2004, 01:10 PM
OK so yea heres the deal. 1996 corolla 1.6l 99,000miles. I have had my car in the shop trying to fix it for the past month (mainly waiting for parts =\ ) and have been unsuccessful. The problem is, is that my car misfires only when accellearating and only in cyl #1. It revs fine and idles fine. I have replaced cap, rotor, wires, plugs, coil, map sensor (this helped prevent misfiring at idle), fuel injector in cyl 1, Fuel filter, ect, cleaned my entire manifold of carbon w/ a can of carb cleaner and egr. I have checked for valve damage w/ borescope and found valves ok and not carboned. Compression at 155-160 all across- thats 15psi above toyota min spec. Checked t-belt and belt is good and tight, but didnt check timing. No intake leaks at all. no exhaust leaks. I added ground wires to engine and ecm and did not help at all. I checked the tps and the voltage sweep is good and no spikes, but when at wot the toyota scanner reads 77%. I tried adjusting the tps but it didnt help the %? The car misfires only when under medium to heavy accelleration. It doesnt misfire when cruising or just a little throttle. It seems though that once the temp guage gets to a lil past the cold like that all power comes to the vehicle. Its like the car gets in closed loop and all the power comes back? wtf??? I am stuck as to whats wrong now? I have had the toyota techs in my shop look at it and they are baffled too. Any help would be much appreciated. Oh, I also have a short ram intake and exhaust but thats been on the car since i bought it.
veedubmechanic
12-09-2004, 01:31 AM
Ok fixed the problem... signal wire from ecm was split in harness a couple threads by firewall causing .8ohms resistance. Too much resistance means not enough voltage to fire injector. Repaired wire and wallaaa car runs better than stock now.... Problably cus I replaced $450 worth of parts lol!
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