Mot smoke test, petrol non cat.
Mot smoke test, petrol non cat.
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courty

Original Poster:

586 posts

106 months

Sunday 24th April 2022
quotequote all
My 1989 Lancia failed mot on emissions.
CO and (HC)3 were way within % and so passed.
However, smoke test was fail.
I looked up mot on gov.uk link to 2017 mot emission doc...smoke test is mentioned only for diesel. For 1975-92 jpetrol ust basic idle emissions, but no smoke test is mentioned.
Is this a new thing for old petrol cars?

courty

Original Poster:

586 posts

106 months

Sunday 24th April 2022
quotequote all
Looking through the gov. document, the smoke test seems to be a visual test after a fast idle for 30 seconds.

If this is passed then the HC3 and CO tests are done. Not sure why they did the HC3 and CO tests if it failed the visual smoke test.

I will ask them tomorrow.

Basically I put some fuel cleaner in and took the car for a thrash...back again tomorrow for re-test.

Here is the fail sheet.



Edited by courty on Sunday 24th April 21:16

V8covin

10,120 posts

222 months

Sunday 24th April 2022
quotequote all
Is the ask an mot tester thread still running on here ?
Might be worth a search and asking on that

paintman

7,860 posts

219 months

Sunday 24th April 2022
quotequote all
www.gov.uk/guidance/mot-inspection-manual-for-priv...
Lists all the petrol defect categories lumped together which might be confusing.

(f) Exhaust emits dense blue or clearly visible black smoke for a continuous period of 5 seconds at idle Major
(g) Exhaust emits excessive dense blue or clearly visible black smoke during acceleration which would obscure the view of other road users Major

AlexRS2782

8,511 posts

242 months

Sunday 24th April 2022
quotequote all
V8covin said:
Is the ask an mot tester thread still running on here ?
Might be worth a search and asking on that
Yep, in GG - link below if the OP needs it smile

https://www.pistonheads.com/gassing/topic.asp?h=0&...

courty

Original Poster:

586 posts

106 months

Monday 25th April 2022
quotequote all
AlexRS2782 said:
Yep, in GG - link below if the OP needs it smile

https://www.pistonheads.com/gassing/topic.asp?h=0&...
Thank you I asked on there.