Hey guys i just bought my 97 240 and i can't pass smog the guys at the shop told me that my cat is missed up before i buy my car i just want to double check with you guys. I don't think it could be my headers or exhaust right? cuz i have hotshot headers and greddy extreme power exhaust. thx guys

 

First run an ecu diagnostic. I am willing to bet that you don't even have a cat. That means more than likely you aren't running a bung and second sensor after what you think could be a CAT. I've delt with this issue so many times on OBD2. You will want to get a magnaflow highflow cat (or what ever you can find that is cheaper) for after the header. Then relocate sensor 2 with a bung after the cat.
I don't know what state you live in so I don't know how much the visual test affects your smog as well.
Edit: you live in socal you will have to pay extra cash to someone that will clear that visual test for you.

 

so a magnaflow would work? and i passed the visual actually i passed everything but the ignition is too high.

 

a tune up is always a good idea before smog, so is removing any carbon deposits on the cylinder head.

high ignition is new to me though i've never heard of that before.

 

i just have 1 question then ... can the magnaflow be a stock replacement?