Will Headers Pass Smog?

Will aftermarket headers cause my car to fail the smog test? Unless the aftermarket headers you purchase and install have an EO stamp, meaning they have been tested by the California Air Resource Board and been issued an Executive Order number, yes they will fail the smog inspection; as a tampered emission component.

Can you pass emissions with headers?

Well-Known Member. Catted headers technically WILL NOT pass emissions because they are not 50 or even 49 state legal since they have been moved from the OEM location. Now, some tuners can set the tune in such a way that when connected to the scanner for the readiness testing they can get you a "PASS" reading.

Will long tube headers pass smog?

"Legally" there are NO long tube headers that are smog legal in CA. The reason is, the cats have to be in the stock location, and obviously that isn't possible with a long tube header. You can have legal shorty headers because the headers stop before the cat, and the cat remains in the stock location.