i just check my timing with a timing gun and i found out that the white mark jumps like every other second, sometime it line up with the mark on the cover and sometime it dont. can anybody tell me whats my problem is? thanks

 

Did you follow the correct procedure for checking the ignition timing, including warming the car up to operating temperature, and then jumping the diagnostic connector behind the pass. side kick panel (very important)? You have to use a jumper wire on the connector, which puts the ECU in diagnostic mode, which in turn keeps the ignition timing constant. Normally the ECU will adjust ignition timing while the car idles to help keep the idle as smooth as possible.

 

my car is a 2000 gsr and i dont have a connector for a ECU diagnostic. however my friend`s SI which have the connector, he check his timing with and without the connector. his car timing didnt jump.

 

Are you sure about that? You don't have a 2-wire diagnostic connector tucked up near your ECU in the pass. side kick panel? I think you should have one.