Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

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Eratosthenes
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Eratosthenes » Mon Mar 08, 2021 8:40 pm

I have read and re read this post with interest.

Due to the current lockdown and having to be extremely cautious because of my wifes lack of immunity as a result of a cancer operation I didn't feel happy travelling 20 miles to the regular garage I normally use for an MOT. A local garage that I have used before for a different vehicle offered collection and delivery. So for today I arranged an oil change and MOT. When my V6 was collected, I breifly outlined the contents of this post, to get the reply I am sure our inspector is aware of this. A few minutes before closing time I received a phone call, probably from the receptionist to say everything was fine apart from the emissions which they will probably sort out tomorrow by giving it a good run. She could not tell me the readings as they were just about to close.
Also somewhere in the conversation mention that the engine management light was on.
I think they have totally ignored my comments about the exhaust emissions test but what I find more concerning why is the light on. Maybe they have engaged the hold button without being aware. However I will be contacting them tomorrow as soon as they open to speak to the MOT Examiner. Is there any reason why the light should suddenly come on at the MOT station when there has been no indication of a problem previously.
I
would really appreciate any comments or suggestions.
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Mrs Feynmans Bongos
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Mrs Feynmans Bongos » Tue Mar 09, 2021 12:37 am

It seems clear to me that your MoT tester has NOT in fact taken on board what emissions limits are applicable to Bongos.

Had they done so, I rather doubt they'd be suggesting a "good run" aka "Italian tuneup", which seems to me unlikely to add anything because Minibus limits are so generous (12x for CO2, 6x for HC I think I said). For V6s known to be running ok, just having the engine warmed up to running temperature (gauge at 11 o'clock) should suffice, but I'm not a mechanic.

The Engine Management warning light is your issue, being now an MoT failure. Perhaps Supreme Beings can tell you what they'd be looking for, given you say "there has been no indication of a problem". Good luck.
Eratosthenes
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Eratosthenes » Tue Mar 09, 2021 2:13 pm

Thanks to this thread and informative posts, i passed on the links posted and guess what - it was all sorted in half an hour. Emissions retested and no warning lights! Say no more.
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Bob » Tue Mar 09, 2021 2:14 pm

Well done. =D>

Great team on here. :D
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Mrs Feynmans Bongos
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Mrs Feynmans Bongos » Tue Mar 09, 2021 6:21 pm

Fantastic news !! (and boy did I need some).

Ok we're lucky that never being marketed in the UK, Bongos never made it into DVLA's Emissions Handbook, so we get to use generous Minibus limits. Just hoping it's too much effort/cost for them to plug this loophole ... as Bongos fade very slowly into history.
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Winnie-bongo » Tue Jun 08, 2021 10:19 am

DVSA have taken note but sadly lots of MOT testers aren't :cry: my Winniebongo has been subject to a full CAT test last two years as my testers say they can't do it without a CAT test 🚐
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by g8dhe » Tue Jun 08, 2021 10:24 am

Perhaps try a different Testing Station ?
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Mrs Feynmans Bongos
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Mrs Feynmans Bongos » Tue Jun 08, 2021 11:07 am

It seems to me unfamiliarity with this scenario is leading certain Testing Stations to "cover their a*se" by ALSO insisting on a Cat test.
(Perhaps understandable, given DVSA impose penalty points on Stations for "Irregularities", too many & they lose their Cert. ie livelihood).

But if they read the extracts from full DVSA guidance I posted above (including flow diagram), read it and understand it, they will see that NO Cat test in addition to "Minibus emissions" test is required, ie they have invented that bit.

Of course trying another Station (as Geoff says) may be easier than trying to walk an Expert-Sceptic through all that DVSA blurb.
Good luck, do let us know how you get on.
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Winnie-bongo » Fri Aug 13, 2021 4:04 pm

DVSA have tried to do as much as they can as the latest reply shows 🙄
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Winnie-bongo
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Winnie-bongo » Sat Aug 14, 2021 9:12 am

g8dhe wrote: Tue Jun 08, 2021 10:24 am Perhaps try a different Testing Station ?
I have stuck with them because I thought it looks better on my MOT history when I sell it which I have been threatening to do the last two years 🙄 so this years MOT had a full emissions test again which also shows that it's running right doesn't it 🚐

I know it's crazy I help lots of people get their Bongo's tested with a non cat test but can't manage my own.
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teenmal
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by teenmal » Sat Aug 21, 2021 11:41 am

Exactly, I dont understand why owners do not want a full test, your vehicle should pass the test if the engine is in good condition, you need to have respect to peoples health . and your pocket.

And .Deborah Meaden isnae my auntie.
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Mrs Feynmans Bongos
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Mrs Feynmans Bongos » Sat Aug 21, 2021 1:21 pm

Hmm, this year MoT station merely gave me a "NON-CAT VISUAL CHECK":
Image

Whereas last year, when I justified use of "Minibus limits", same station gave me "NON-CAT METERED CHECK":
Image

After having first failed it on "CATAYLST EQUIPPED WITH CLC":
Image

Only 12 days ago, so reckon I'm going back to demand a full CAT-TEST but with MINIBUS LIMITS (which I thought I had, grrr)

Thanks again, such a helpful lot on Fury!
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Brownz » Fri Jun 10, 2022 7:56 pm

So, My V6 Petrol also failed on one thing at his yearly heath-check. Seems to have gaseous emission problems - much like his owner.
It had a mini service when I got it in June last year comprising of new plugs, new HT leads.
I fitted a new air filter in April this year where I also cleaned the MAF sensor.
It had a cambelt service about a month ago where it also had an oil change, oil filer etc.
When it failed with such a big reading I fitted a new Lambda sensor, no change even when nice and hot. (I have a little Gunson gas analyser which gave the same reading as the MOT station).
Any suggestions on where to head on the diagnostic trail next ? All input welcome.....
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Brownz
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Brownz » Sun Jun 12, 2022 11:52 pm

Stripped the airbox off to inspect the flexi pipe, clean the MAF sensor and its plug again today.
Ran the gas analyser after getting it nice and hot.
Fast idle it shot up from 2.0% to about 7.1% - 7.4%, when throttle was lifted it dropped down to about 2.0% again - which is a pass for the non-cat test (3.5%). Whilst stood there scratching my chin and wondering what to have for lunch, about 15 secs later while idling it jumped up to around the same 7% reading. This is odd, because it runs like a dream, alway been silky smooth, never smokes,never loses any coolant. With a jump like that on idle I would expect it maybe to hunt as its over fueling, but nothing, just the O2 reading worse than a cow thats been out for a vindaloo and 20 pints of lager. Got a new cat coming on Tuesday. Will see if that helps.
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Re: Diagnose more V6 emissions? (CO,but Lambda seems fine) DON'T DELETE

Post by Bongolia » Mon Jun 13, 2022 10:47 am

You should also check the Coolant Temperature Sensor as this may be faulty and giving a "cold engine " signal to the EMS. This is not the same as the temp sender, fitting a new cat with a 7% reading will damage the new cat in time. Readings need to be at least the same as for a non cat engine prior to replacing the cat.
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