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Going catless and emissions testing

Old 02-23-2016, 01:23 PM
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Going catless and emissions testing

All, I have a 2014 JCW Clubman and I am planning on installing a catless downpipe. Has anyone done this? Does getting a Manic tune allow me to pass the emissions test despite being catless?

Thanks for the help here!
Old 02-26-2016, 05:39 PM
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I'm going to take a shoot in the dark at this one. If I am correct your downpipe has a sensor in it followed by a sensor mid way down the exhaust. Anyone correct me if I am wrong but I believe if you go catless in the downpipe and still have a sensor there then the test won't pick it up. The second one mid way does that. The first sensor is for A/F ratio. Like I said someone correct me if I am wrong.
Old 02-27-2016, 04:59 AM
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But without the cat, the second sensor will throw a code because it will show
that the (missing) cat is not doing its job. In PA, this will fail the OBD emissions
test, as will a visual check. It appears that IL has OBD type testing like PA.
If you live in a state with a tailpipe testing, it will probably fail as well.
Old 03-01-2016, 06:46 AM
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gone catless -- and STILL passing emissions 4 years in a row!

IL emission tests are a complete scam.. I've been on a long tube header with no cat, no resonator and barely a muffler. I'm actually still on a factory tune, with a slight modification to the location of the secondary o2 sensor installation. I've been to emission testing 3 times, passes every time. According to IL standard testing, the car is allowed 1 un-ready readiness monitor. (guess which that one is for me!!) The only time I have ever thrown a cat fault is when I let my buddy drive the car... apparently he doesn't drive it like he stole it..
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