I need help/advice regarding a 2008 chev malibu that the engine light stays on. It was coded indicating its the catalytic converter which has been changed out twice. The CO2 sensors have been replaced as well. And the car has been reset several times.. This car can't pass the smog text until this is fixed. Aside from blowing it up does anyone have any suggestions? Already dumped enough money into it. Tia

 

code was what p0420 p0430?
post a link to the cat you bought. Cheap cats have low cerium content and the low efficiency dtc will just reset.
if you replaced the rear 02 and have an old front 02 the code can set from a lazy front 02.
The code sets based on 02 cross counts....so if both 02 are new and switching normally....its most likely a bad new part cat.

if the cat is a high quality part check with the dealer for possible pcm reprogramming update

 

the code is P0420. All sensors have been replaced. Someone mentioned maybe the gas cap doesn't have a good seal?

 

p0420 has nothing to do with the gas cap or evap system. who ever told you if was related knows zero about cars.

 

Thank you for clearing that up. So, if the code is p0420, and all sensors replaced, and new cat, do you have any other suggestions? This is truly stressing me out.

 

did you put a cheap cat on? post a link to what cat you installed

 

I dont know what he put on. Car going back on Friday and I will definitely ask.