MOT CO2 emissions

[brentstevens]

99V reg Chim 4.0. Just failed MOT due CO2 reading just over the level but other 2 exhaust readings were fine.
Mileage is 32K with only 2K last year. Car has not been run for about 4 weeks although local garage (who passed it last year with no probs) ran car until fans cut in so engine was warm.
A thought - could the Cat and lambda probes have "sooted" up and would a prolonged blast at high revs, then measure the CO2 levels solve the problem?
Any thoughts out there?

[Tyre Smoke]

Hoof it for at least 10 miles, then switch on every electrical thing you can and get them to take a reading.

[edward1]

Check the garage is using the right levels. When I had mine done although it just passed. They did notice that machine was pulling up the normal limits and not changing them. Hence a near failure. In the ministry book listing the limits for all cars there was a wider range allowed on TVR's than your standard eurobox.

This was on CO I think. For most vehicles it pass/fail limits were 0.97%-1.03%, where as for the Chim the limits were 0.9% - 1.1%

Just a thought

[chimtvr]

the emissions laws are the same for every car built since august 1992 no matter what make. copy down exactly what the printout says and i will tell you what the problem is
the only thigs that will make your car fail are carbon monoxide (co),Hydrocarbons (Hc) or Lambda co limit is below 0.3%
and lambda limits are between 0.7-1.3

[Mr Jenks]

chimtvr said:

lambda limits are between 0.7-1.3

I think that should be 0.97 - 1.03

[chimtvr]

yes sorry my mistake after a day of mots i was tired i only really look at the last digits

[brentstevens]

Well - after about 30 miles of quick motoring and keeping revs well up so the cat was very hot , went back to the garage for the retest.
Bugger - it still failed the CO emission if revs were below 3000. At 3250 revs, it went below the limit. Holding the revs at 2900 (as near as possible), the CO was just over the limit. The other readings were perfect.
So now have it booked into a specialist to solve the problem. Lamda probe problem??

[brentstevens]

Problem solved. After a £160 run on a specialist "computer thingy", it turned out to be a dodgy connection to one of the Lambda probes.
Sailed through the MOT. No probs.
Expensive to find out that bugger all was really wrong - just a waggle needed - but that's the only problem in 2 years of Chim ownership.
Can't complain - and I'm thinking of going the Tuscan route. Must be barking?

[big.jezz]

if you go and get the tusc just make sure its had the rebuild with the new spec or get a new one and all will be fine

[jem]

here we go...



J