+4 failed MOT on emissions

Technical queries or suggestions

+4 failed MOT on emissions

Postby Mike Hughes » Mon May 18, 2015 6:01 pm

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
Mike Hughes
User avatar
Mike Hughes
 
Posts: 75
Joined: Sun May 17, 2009 8:47 am
Location: Odiham, Hampshire

Re: +4 failed MOT on emissions

Postby Philip Tisdall » Tue May 19, 2015 8:40 am

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.
Philip
User avatar
Philip Tisdall
 
Posts: 364
Joined: Thu Dec 15, 2005 6:10 pm
Location: Warwickshire

Re: +4 failed MOT on emissions

Postby Mike Hughes » Fri May 22, 2015 7:50 pm

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
Mike Hughes
User avatar
Mike Hughes
 
Posts: 75
Joined: Sun May 17, 2009 8:47 am
Location: Odiham, Hampshire


Return to How do I ?

Who is online

Users browsing this forum: No registered users and 1 guest