I got the CEL the day after I bought it. I got it reset just to see if maybe it wouldn't come back but it did.
My AutoZone printout reads:
Definition-
Catalyst efficiency low bank 1
Explanation-
The oxygen sensors monitor the catalytic converters ability to store oxygen.
Probable Causes
1. Catalytic converter defective (failure possibly due to #2, 3 or 4)
2. Engine misfire or running condition
3. Large vacuum leak
4. Engine oil leage into exhaust valve guide seals, piston rings.

Now number two, to me, looks like maybe I could take these Bosche spark plugs out (that were included with the purchase), and install the OEM which will be in tonight. Other than that I looked for large vacuum leaks and saw nothing. So does anybody have an idea? Maybe somebody out there has dealt with this. Thank you.

 

Could just be what it says, catalytic converter has gone bad. Did you just get this car? There's no test pipe on it, is there?

 

Yes. I just got the car and it looks like it has the cat. I have hopes that the cat is not bad.

 

Maybe just the O2 sensor along with the CAT. Many have had the problem and the cat has been revised in later models... here is one of a number of threads.

https://www.s2ki.com/forums/index.php?showt...0&#entry6015677