maddawg

have a 06 Cobalt 2.2 with a engine light that keeps coming back on. code is P0411 and P2440, both related to the Secondary Air Injection System. So far been to a Chevy Dealer 3 times and spent over $800 in repairs. Air Pump, Check Valve w/gasket and Mass Air Flow Sensor have been changed. Any Ideas or advice would be helpful Thanks !!

maddawg

Dealer finally got it right, the air pump they installed failed due to a bad check valve. even with a new pump the check valve was stuck causing the pump to fail. new valve and pump at the same time fixed the problem.

BHBarr

I've had the same problem. I bought a 2006 Cobalt new in June 2006. Got the engine light on with code P2440 in June 2008. The check valve was rusted stuck open. Replaced it for $210 parts cost. In March 2009, light came on with codes P0411 and P2440. This time the air pump was rusted frozen. Replaced it for $200 parts cost. In September 2009, engine light came on with code P0411. The check valve was rusted stuck closed. Since stuck closed did not affect drivability, I left it until I failed emission inspection and had to replace it last week for $260 parts cost. I have no suggestions - I think the check valve lets some exhaust leak through, which causes water to condense in the tubes, which in turn leads to rusting of both the valve and the pump.