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Q: Catalytic failure identifying the cause

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My 1996 Ford Taurus Wagon has Cat Efficiency code P202 I think!! Has been like this for years!! It is no longer my daily driver but I want to analyze the source of the failure!! Many mechanics state that Catalytic Converters don't just die, they are murdered?? If that is an appropriate assumption, what diagnostics must I perform to determine if the repair is justified. Engine starts immediately and does not appear to be burning oil.. ODO broke at approx 62K and car may have as much as 200K but well maintained. As of late when I drive the car you can smell an unusual odor as well as temp gauge swing..-
My car has an automatic transmission.

Hi there. It is possible for a catalytic converter to wear out over time and if the engine has misfires or oil consumption, sooner than later. The trouble code most likely is a P0420 and/or P0430. These are catalyst efficiency insufficient codes Bank (1) and (2) respectively. Most of the time, it is the catalyst that has failed, although an exhaust leak or faulty O2 sensor could set these codes. Justification for repairing this fault, would be to lower emission levels and turn off the check engine light. If the computer recognizes another fault, you would be unaware, as the check engine light is already on. The unusual odor and temperature swing may be a coolant leak has developed. I recommend having your vehicle’s possible coolant leak and check engine light on be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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