I just put on an ITR cat on my 00 LS, and now its throwing a code 67 CEL. i believe this is the catalyst inefficiency code. 94civicEx linked me to the FAQ thread but the names of the codes arent the "official" names for some of them.

Do any of you know why it would do this, aside from the cat or 02 sensor being bad? Like any incompatibility issues (too much flow for an LS etc) or something of that nature?

Thanks in advance.

 

This is what the code says: "Catalyst system Efficiency Below Threshold malfunctioning or defective catalyst system."

It has nothing to do with flow...high flow cats/test pipes don't throw codes when the O2 sensor is in correctly, and they flow way more than an OEM ITR cat. It's possible that the cat you got is bad...either clogged/poisoned, or the catalyst is loose. If you take the cat off, you should be able to see through it. If you shake it and it rattles, then the catalyst has broken loose and will not function.

 

This is a used ITR cat I assume. I just recently installed a Carsound high flow cat on my LS with no CEL. You never know what your gonna get when you buy used.


werd

 

thanks guys, i got the cat from a friend. i know its good, because it came from his car and he had no problems. it was in good storage as well. i believe i know the problem....and i will share it when i verify it...

but my main question was answered (flow characteristics).