[dday216]

I just installed my FC 3 piece underdrive pulley set. They work great but my check engine light keeps coming on. I disconnected the battery so my computer reset 2 time and the light come on after 20 so miles. I don’t know what to do about it. I installed them like it said on the instructions. Should I find out what is going on or keep driving and not worry about it and find out latter.
thanks

 

[Wedge1212]

your o2 sensor is out...usually 02 sensors throw a CEL after 20 miles...check all the connections first...but to be 100% take it to autozone and have them pull the codes.

 

[phillyesco]

egr valuve. how many miles you got?

 

[dday216]

like 600

 

[Blue01Street]

Another common one is the DPFE sensor. I've had 2 bad ones.