2002 Toyota Corolla catalyst efficiences below threshold
MLSMC
MEMBER
2002 TOYOTA COROLLA
Computer problem
2002 Toyota Corolla Automatic 157000 miles
I have this check engine code: catalyst efficiences below threshold
and I am told to put gas treatment in my tank and it may fix the problem. Is this good information?
Tuesday, December 9th, 2008 AT 8:14 AM
1 Reply
MMPRINCE4000
MECHANIC
8,548 POSTS
It is more than likely a bad O2 senor(s). Especially if they have never been changed.
Before changing them have a backpressure test performed on the CAT to see if it is clogged or partially clogged.