I installed a cold air intake on my car. Would I still be able to pass smog inspection?

Question

My car is a Honda Civic 99 EX and recently changed the headers too. Would all these changes affect whether my smog inspection pass or fail? and how come?

Answer 1

If your state's smog inspection includes a visual inspection (as California's does), then you will fail the visual inspection, because it will be obvious that the CAI and exhaust header are not factory original.

Also, if you have changed the exhaust header and removed the pre-cat (catalytic convertor embedded in the exhaust header by the factory to improve cold-start emissions), then you might fail the emissions test, especially if the car is not fully warmed up when you test (or if the lack of an O2 sensor throws a check engine code -- common when a pre-cat is removed, if you skip installation of a "dummy" sensor to prevent the code.)

Now, there are a few exceptions to this:

1. If your state does not include a visual inspection, your car's emission output meets the requirements, and no check engine code is thrown -- you'll pass;

2. If your state does include a visual inspection, but the person doing the test is sympathetic and willing to lie about it, your emissions meet the requirements, and no check engine code is thrown -- you'll pass.

Many people who install their own CAIs and headers actually pull the units out and put in the stock units every two years for the inspection, then swap 'em back afterwards.

The good news is, in most cases if you fail, you can simply drive away, put the factory goods back on, and get re-tested. From the state's perspective, you "fixed" your emissions problem (assuming it then passes the emissions test.)

EDIT: Note about "header" vs "headers", as mentioned in someone else's answer: if you have a chevy V8, you have one intake manifold and two exhaust headers. If you have a honda inline 4, you have one intake manifold and one exhaust header. However, it is common parlance to refer to the set of intake manifold and exhaust header as "headers", at least where I live. Nevertheless, I changed my answer to specify "exhaust header" for clarity.

Answer 2

As long as the parts you install have CARB exemption numbers, particularly, your header (by the way, 'headers' implies more than one, as on a V6 or V8. Your car has a header.), then you should have no prob. Be careful, though, some aftermarket parts are NOT smog-legal. As long as all of the emissions components are still on the car, (things like the O2 sensor and air intake temp sensor), you should pass the sniffer test just fine,

Answer 3

save youre money for something that matters,research it and you will find it really doesnt do a thing for power or mpg. How can companys justify the price they ask for a filter and a piece of pipe with a 90 degree bend in it anyway? Where is this--cold -- air coming from ? about a foot away from the factory location,think about it. Just my 2 cents

Answer 4

Yes it will still pass all that should stay the same! Let me warn you though sometimes those cold air intakes can mess with the computer on you car! Happened to me!

Answer 5

thats depends where live, in some states yes you would fail, but most others you would be okay, the best thing to do is check the law at your state police website

Answer 6

You shoulda thought about THAT BEFORE installing the thing EH?

Answer 7

yes.