2001 dodge status 196000 miles check engine light on.autozone diag,says 02 or cat,converter which one?

Question

only misses at steady speed or with cruise on slight smoke at idle

Answer 1

With a car that age and with the miles I would not be surprised that the cat has deteriorated but the sensors could also be bad. Especially when the 02 sensor is in the cat and on those vehicles I think they are. There really isnt a way of determining which one is bad unless it is looked at by a mechanic. The 02 sensor can be tested and the cat can be checked for deterioration or carbon build up.

Answer 2

There are many components that work together in the engine to maintain optimal engine performance and economy.
A service engine soon, or check engine light indicates that there is a sensor that is reading a condition that is "out of range".
Simply resetting the light does not solve the initial cause of the problem.
Replacing a number of parts trying to troubleshoot the problem in the hopes of getting the light to stay off is a tremendous waste of time and money.
The simplest, and most economical way to alleviate your issue, is to have an engine diagnostic done by a reputable shop to determine what caused the computer to signal you to begin with. Just reading the computer codes may not find the "cause".

Answer 3

The O2 sensor is normally changed with the oil change schedule as this affects the engine performance, as almost all engines are computer monitored in fuel mixture. The cat converter is normally not changed unless you plan to keep the car longer than a decade or if you have been using a really cheap gasoline. Exhaust gases can not flow freely if the cat/con is clogged with the build up of the unclean fuel, like the fuel ports or intakes. I changed my cat/con on my 93 Escort and it did improve engine performance, but since I changed the cat/con, it made sense to change the muffler also.