Q: Every three months, catalytic converter and muffler must be replaced

asked by on August 15, 2016

The catalytic converter and the muffler have to be replaced every three months in my SUV. The cause of this is the hydrocarbons that are continually deteriorating them, but I do not know what is causing this problem. Using Bosch products, I replaced the wires and the plugs. Also replaced the EGR with an AC Delco. But not a solution; problem still exists. The catalytic converter becomes clogged up and then will not accelerate very well at all. I’m considering that the only way to go is straight pipe before junking this SUV. Do you have any suggestions of how I can fix this and save this vehicle?

I would start with checking the O2 sensor. This is what relays exhaust gas changes to the vehicle’s computer. When this sensor is not working correctly, incorrect or misdiagnosed air/fuel mixtures are relayed to the vehicle’s computer causing incorrect changes to be made. When exhaust vapors become trapped in front of the catalytic converter, this can also cause a misreading by the O2 sensor resulting in a misreading to the computer. I would recommend having a qualified mechanic, such as one from YourMechanic, come to your home to diagnose the acceleration issue and pinpoint the cause of the catalytic converter problem.

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