Author Topic: Emissions fail on 8v  (Read 1424 times)

Offline owenfranssen

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Emissions fail on 8v
« on: 18 August 2013, 21:58 »
My 8v failed its MOT (actually the Irish equivalent) on a couple of things which I have ordered parts. However one of the fails was on emissions, which I know little about. Lambda passed at 1.01% , as did the HC at 65ppm. But the CO was at0.41% and failed as its meant to be .3 or under. Any suggestions as to what I can do to remedy this?

Offline dibs1980

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Re: Emissions fail on 8v
« Reply #1 on: 21 August 2013, 21:59 »
Maybe try some injection cleaner, pour it in the fuel tank and give it a REALLY good hard run before you take it back for its re-teat basically the hotter the engine the better.
If that doesn't cure it its a new Cat converter I'm afraid

Offline itavaltalainen

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Re: Emissions fail on 8v
« Reply #2 on: 22 August 2013, 12:14 »
pour 1l of 99.9% isopropyl alcohol in the tank.... if you got any E85 filling stations add around 30-40% E85 to your fuel...
drive it for a while (50km), then retake MOT (with well warm engine before you hand it to them), ask the tester nicely to drive it round in 1st at 4000 rpm for 1-2 minutes before the actual test.

adding IPA helps to clean injectors etc (much cheaper than injector cleaner products and it's the main ingredients of those things anyway!)
running on higher content of ethanol in fuel lowers emissions... when I used to live in Finland I always ran my car on 30-40% alcohol for one tank before doing 'katsastus' = MOT, same when I went for the emissions test. always passed with flying colours (it had well over 300,000 km on the clock with first cat).
2019 Seat Leon ST FR DSG 135kW - eclipse orange - 23k miles