Will this throw a check engine light?
 

I found out today that my car is California emissions compliant (I'm in Arizona). If I put on a 49 state catalytic converter on a California compliant car... will my check engine light come on? The guy at the exhaust shop said it will. Also the guy at the exhaust shop told me it was illegal to put at 49 state cat on a California compliant car.

What's going on?!?!?! I have a 49 state cat coming in the mail tomorrow so I'd like to figure out what I can do soon.

Thanks

where do you live, and what car is it? im not familiar with the cali emissions package, but i dont think it would throw a code if the cat is functioning. the post cat 02 sensor reads cat efficiency. if it has to be tail pipe tested, thats when you might run into some issues

I live in Tucson , AZ. 2001 3.8 And there is no tail pipe test on my car because last time I did emissions... all they did was hook up a wire to the OBDII thingy... and then said I passed:)

As long as the Cat has A.I.R. fittings....

I just did a little research and I still don't know what that is... what are A.I.R. fittings?

Part of the enission control system...

there is an air pump for the a.i.r. system. it pumps air into the cat for less emissions. im not sure though with it being a cali car if it will throw a code or not.

who gives a rats tail if it's illegal, as long as they don't catch it, my 92 gmc doesn't have any cats anymore. That being said the only way it'd throw a code is if the o2 censor behind the cat reads different oxygen levels then your pcm thinks it should read. because the oxygen sensor can't tell if there are more/less emissions per say, just the level of oxygen, so if there are more emissions there will be less oxygen, the catalytic converter has several catalysts that convert harmful emissions like co hydrocarbons, into harmless emissions like co2 and o2. SOME cats are more efficient than others, some last longer than others, and very few convert NOX emissions to something idk exactly what. the california one probably does have a catalyst for NOX and the 49 state one probably doesn't, whether it'll actually set a check engine like or not, i don't know.

if it does throw a code, just get it tuned out. And if your test only connets to OBDii port and there are no codes, its not a prob. I dont know the difference between the cats in cali and rest of US, i dont even know which type i have on mine, a UK import???? But soon enough i wont have any :D

Just so everyone knows there was no check engine light and everything is fricken sweet!