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+4 failed MOT on emissions

Posted: Mon May 18, 2015 6:01 pm
by Mike Hughes
My +4 road car just failed the MOT due to emissions. It has massive CO and HC levels and is clearly running very rich. With the standard ECU having no adjustment I assume it must be a sensor driven situation. I've replaced the pre-CAT lambda, but it's not that; any of you clever people got any ideas?
All help welcome....
Cheers
Mike

Re: +4 failed MOT on emissions

Posted: Tue May 19, 2015 8:40 am
by Philip Tisdall
Mike,
It is a problem I had with my +4. All I can suggest is that you give the car a really good run so the exhaust system is really hot when they test it and try and avoid letting it tick over before the test. I use a garage that tests a lot of “old” cars and they know the issues that these cars have. So maybe go to a garage that is use to testing these cars.

Re: +4 failed MOT on emissions

Posted: Fri May 22, 2015 7:50 pm
by Mike Hughes
Thanks Phil,
I managed to fix it today, it turned out to be the EVAP valve being stuck open, it was causing the emissions and rough idle.
It passed the retest at a CO of 0.004.
Thanks for your interest.
Cheers
Mike