I installed my Greddy EVO2 cat back exhaust about a week ago...sounds and feels great, but after only a 100 or so miles my SERVICE ENGINE LIGHT is on...please help.....I resseted my ECU using the accelerator method but the light came back on after another 100 or so miles During hard acceleration...

You can search around for how to read your ODB2 system/pull the code and determine what is wrong.

Found a link for you

http://www.infinitihelp.com/Ownership/Common/codes1.htm

I got it from the DIY from madchef.

Coupe or sedan ?

thanks for the code list link....

04 coupe 6 speed........is there a reasonably priced OBDII scanner?