2000 Grand Am SE1 2.4 Quad 4 Problem # 2

[melsg5]

The details on those O2 codes list a number of possibilities including bad wiring harness and exhaust leaks. In addition poor aftermarket sensors can cause issues.

 

[Natelee1386]

I have scanned this car and found a couple codes for O2 sensors, and a couple for EVAP system. No big surprises there, but shouldn't I have a check engine light on for these? Currently not lit... WEIRD.
Second, I am wondering what normal idling RPM's are for this engine. I currently show 600-650 when temperature is reached. I'm thinking it should be 100 or so higher.
Any thoughts on these 2 circumstances? Thank you in adavance to all on here for this informative message board.

Does your check engine light come on when the key is in the on position with the engine not running? If not your bulb is burn out.

 

[Clutch_Dance]

Its not burnt out. It lights during dash-test phase upon starting.

 

[Clutch_Dance]

Donut gasket @ manifold exhaust down-spout leaking, Introducing air to both O2 sensors. I should have remembered this triggers that.