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What exactly is the IM240 emissions test?

JBsC5

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Nov 28, 2001
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Location
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What exactly is the IM240 emissions test?
I know California and several other states use the IM240 test or higher which will more than likely fail a car that has a cam installed.

What is this test and is there any way around it?

I am concerned about passing emissions in NJ ...

Can someone please explain this test?

Thanks in advance.

JB
 
Don't know the specifics of the IM240 test; however, if you are considering installing a new camshaft, get one with a CARB exemption. That way, the vendor of the camshaft is responsible for any problems in passing the emission test that are related to the camshaft.
 
Im240

I can explain most of it.

On OBD2 equipped vehicles (1996 and newer) there exists a self policing emissions set of tests, if you will, internal to the code in your PCM. With that said, your emissions test is all about not showing any SES indications such as DTC codes and you'll be fine.

What people run into with cams, occasionally, is that they don't get the car tuned to compensate for the irratic misfires that occur as a result of the more aggressive cam. Most cams will create a misfire code if the PCM is left alone so it's a good idea to get your car tuned professionally for any cam. That way you can pick a cam that makes power and not sacrifice anything in trade for passing emissions.

The IM240 test checks to see that your PCM ran and passed ~9 tests related to emissions. Things like CAT test, to see that your cats are functioning properly, Misfire test (self explanitory), EGR (you're exempt), etc. These tests occur naturally as your car is driven through all paces of road experience, including, hwy, in town traffic, stop and go, and idle. All this occurs without your knowing.

The bottom line / beauty is that you may add as many go fast mods, cam, heads, blower, NOS, etc as you want. It just needs to be adjusted for the mods via the programming and you'll pass.

Sorry for the long wind there.......;)
 
Thanks Brian..

That was far from long winded but rather information..

Its very clear now..

Thanks

JB
 

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