2001 Saturn Sport Coupe

Engine Performance problem
2001 Saturn Sport Coupe 4 cyl

i have dtc p1635. That code doesnt tell me much. Is there a flo-chart or any info on where to start. Where is circuit 1?
June 18, 2009.

Only have seen that code set as a flase code meaning that it was set without an actual fault for the parameters to set it. What I was told when asked yrs ago from saturn tech assitance was it was set if the key was rotated off and on too many times in a row to fast.I have reset those codes and the customer never came back so I learned to ignore those codes when it was just that code. Is that the only code u have?

Nov 16, 2009.