I have a 1990 Toyota pickup that needs a catalytic converter. It was purchased in California with CA emissions but is not registered there. Can I use a non-CA catalytic converter and not have problems like the check engine light coming on? Big difference in price.

 

Only difference is the cat has met California's quality restrictions. Which means they paid for an exemption order number. Run either one. The second O2 sensor is just a cat efficiency sensor. It does not adjust fuel trim. So even if the CEL comes on for cat efficiency, it will not harm anything (unless cat is clogged) or the environment.

 

I am not 100% sure, but running the non-C.A.R.B. converter should be just fine. Like SENOR NOODLES said, the oxygen sensor after the converter is just a monitor that checks if the catalytic converter is working.

 

I don't want to put in a new catalytic converter and have the engine check light come on for the effort.

 

Took off the old catalytic converter and discovered I bought the wrong one. Punched a hole in the old one and put it back on. No check engine light yet.