Pontiac Repair: Pontiac Grand Prix 2006, pontiac grand prix, cat converter

Question
Hi,I have a 2006 Pontiac Grand Prix. Two months ago my check engine light turned on, I then to it to the mechanic and they told me it was the catalytic converter. They changed it. Then it turned on again and they told me now it was the exhaust pipe.And the ecibor. after they changed a few days later the chek engine light turned on again! I took it them again and they changed the exhaust manifold gasket. Then they changed the sensors. And then again the check engine light turned on again two days later.Can you help me know what it is?

Answer
Hi Pedro;

do you know what codes is setting? same as when this all started a p0420? first off if an aftermarket converter was put on this that is more then likely the issue and nothing else. if it had an orignal equipment (new) not used converter and it keeps setting the same code they need to look outside the box as to a cause but 99% of the time a cat. converter codes is cause by just that the converter. if afermarket sensor were put in this same thing they cause issues. No afetrmarket parts for any fuel injection/fuel related parts should ever be used. good luck ;-)