I recently installed the Greddy turbo kit onto my 99Si and all was great until yesterday. I drove around 250 miles before the CEL came on giving me codes 71,72,73 which is the misfire codes. I checked the plugs and they look great. The car seems to idle and run just fine...just that the CEL continues to come on. If I pull the 7.5 backup fuse the light goes out for about 5-6 hours then comes back. I understand there are quite a few Greddy users who have been getting the misfire codes when nothing seems wrong. Anyone have any ideas on what is tripping the ECU into the misfire codes? It seems to come on when I start it after sitting for a while. Someone mentioned that the ECU doesn't like larger injectors and distributes too much fuel when starting. Anyone have the same problems?

 

a lot of the reason of misfire is just minor problems such as caps, rotors, wires or it can be the plugs that it is not gap right...try to check those...if it still comes on...try adjusting the fuel range maybe if check the plugs and u are running too rich try bring down the pressure a little bit...hope this helps somehow