sup guys..i have recently installed some itr headers and exhaust on mah 99 gsr and after that my car started to idle funny and the ride was all weird....then after 2 weeks ago my engine check light came on and i checked the codes and it was 45 which meant the system fuel is too rich or lean.......wut could be the problem? o2 sensor possibly?

 

o2 sensor mostlikely<<check ur connection<<

 

agreed

 

You might want to reset the ecu and let it relearn before driving it. The ecu needs to relearn and adjust for 10-15 minutes to each change with intake/headers/exhaust that you make. To relearn you unplug the battery to reset the ecu. It usually takes 10-15 minutes on my car. Then plug it in and start your car. Don't have the stereo on, headlights, air, any power drawl at all. After 15 minutes take it for a spin and see if that helped any.
HTH
Nick

 

well i already rested mah ecu like 3 times already, didnt help......the funny thing is mah check engine light went off......but im still having problems.......i honestly think is mah o2 sensor......but who knows......thans ne way guys

 

I am having exactly the same problem...car idles bad but runs good up to 1500 rpm....reseting the ECU made the engine light off b ut didn't help so I changed my O2 sensor....runs good now

 

mah=my? sorry not up on the ebonics lol