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Catalytic deficiency light

Looking into buying a 2001 Corolla, but Check Engine light gives code for ‘Catalytic Deficiency’ - We’re told they don’t know if theres an actual problem w/ converter, or if replacing it would fix problemm, or if there even is a problem. Any thoughts?

How about getting the actural problem code. It should be something like P0123.

If you don’t have the number, some auto parts stores will read them for you and give you the results free.

Generally those codes lead to a bad sensor or a bad converter. Has your car been burning oil? Do you add oil between oil changes? How much?

Those cars are everywhere, you shouldn’t even think about buying a problem. Get one that doesn’t have something wrong with it. Nobody is sure where the problem is; they would just have it narrowed down to a particular system. The buyer can beware before the sale. Better than waiting until you own it. Forget fixing it and walk away.

One never knows if the converter has failed due to a far more serious problem.
A car that is seriously overheated may develop into an oil burner. This burnt oil will cake in the converter and on the O2 sensors and replacing these items may not solve the root of the problem - expensive engine work.

Not performing regular maintenance or driving it for months on end with an engine performance problem can do the same thing.
As with any used car it should be closely inspected before buying it.

It’s also possible the seller may know there is a serious problem and is simply playing dumb with it.
While car salesmen routinely get vilified, and often with good reason, a car sold in a private sale is not immune to some BS and flat out lying either.

You would be surprised at the number of people who receive bad news about their vehicle from a mechanic and choose to dump it on an unsuspecting dealer or individual; all the while pretending to be ignorant of the problem.