3 months ago i break my gearbox. after i changed it with a 2nd hand gearbox, i started to have some misfiring proplems when car is cold and over 1.3 bars boost.
i installed new sparks, wires, distrubutor cab, rotor arm. and i still have this damn proplem.. dont know what to do. did any one experienced some thing like this.?

does the car idle properly ? , it could also be that ur knock sensor is bad ....but then again are u getting any engine error codes ?

This post has been edited by Gmoney1: Feb 17, 2007 - 10:57 AM

how many miles are on your coil and ignitor?
since youve only started to notice the problems after the tranny swap...have you checked all your grounds?

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car idle good when its hot. no any ecu errors

when i had a misfire at idle and hesitation i went through every single thread on mr2oc and tried everything.. well one day i finally figured out that my pigtails for my injectors were worn and not making good contact, pushing on the pigtail would make it stop misfiring so i ended up replacing the pigtails..

id suggest first finding out which cylinder is misfiring by pulling out the spark plug wire and seeing if the misfire pattern changes, then from there check the pigtail

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i ll try this tomorrow. i was talking with a friend of mine that he is mechanic. he said it is not an electrical proplem. may be a hose leaking air to intake manifold. of from injectors. beacuse car has some black smoke and eating to much petrol.

what a/f ratio do you see in the cold weather? what is your ECU telling you? you should be able to log all kinds of stuff and pinpoint the problem.

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Whoa... are you saying when the motor is cold, or when the air temperature is cold?

You should NEVER get anywhere close to full boost of the motor isn't fully warmed up.

If you are just talking air temperature, then follow the suggestions of the others on this threa.

-Charlie

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man .. i dont even move my car before car warms up..
i was talking about when car is cold...
but just talked with my engineer proplem is solved. he mapped the car again little adjustmenst on distrubutor. and its ok now.
car can boost up to 1.7 bars now.
cant wait to drive it...