I got a 5th Gen Prelude ('99) and I live in California. This is the first time I've ever had to do a smog test so I've been looking into it, but am still unclear on some things. I already know I'll fail a smog test because I have a couple exhaust leaks right after the cat, right where the rear O2 sensor is. The Rear O2 sensor is also bad and is tripping the CEL. The cheapest place I've been quoted on to replace the cat & O2 sensor is around $400. For that much, I can get a cat-back system + cat + O2 sensor that is all bolt on, and do it my self.

I know that the cat has to be specifically CARB compliant, but what about headers, muffler, and the rest of the exhaust system? Will having aftermarket cause me to fail, even if its able to pass the sniffer test (which as far as I understand is completely dependent on the cat)?

Here's the cat-back system I'm thinking of getting. The cat is a Magnaflow, and I know that will work, so not an issue there.




Thanks.

 

Why do you people never call the ref station and ask these questions?

 

Replacing anything after the cat is fine. You will be OK for smog. You of course need to have an operational cat. Smog guys don't care about dB limits but LEOs do sometimes.

That means no on header unless it's CARB compliant.

 

The secondary O2S is located in the catalyst. If the catalyst is rusted out then the O2 will pickup the false air and is probably setting the code. That O2 only checks that the catalyst is functioning, if there are holes the catalyst will not function correctly.
If non-factory header does not have an E.O./C.A.R.B. approval then it it will not pass SMOG. Same for catalyst.

After cat there is no need for E.O./C.A.R.B. approval, but does have to meet db levels. Most 'street legal' bolt in systems will meet the db requirements.

 

Thanks guys. Really helpful. I think I'm going to go ahead and order the cat-back system. The Cat itself is approved for California and has the correct executive order number that corresponds with my engine family number, so no worries there.

Can anyone post some picture of the stock cat/exhaust system, and dimensions of the stock cat? It would be really helpful. Someone replied to another thread I had in regards to the length of the stock cat, but didn't specifiy if it was for base or SH. Not sure if there's a difference for the cat, I know the SH has a longer down pipe though. My lude is just the base model.

 

Online searching is better. The Ref station does not take calls and visits are by appointments only (made on the automated system when calling)

 

Try the Magnaflow website. They are good about what cats can and cannot be used in CA. If it is not on their website,it is likely not CARB legal.


Headers need to be CARB legal to pass. (EO number)


Everything else can be generic.