what is the "Smoke Opacity figure " for 2005 Audi A3 WAUZZZ8P56A036799 BKD PD 2l TDI engine

[gordon123123]

Hello and hope some one can advise you can help please , MOT smoke test


what is the "Smoke Opacity " for 2005 Audi A3 WAUZZZ8P56A036799 BKD PD 2l TDI engine i cant work it out from plate behind expansion tank



MOT Garage is saying the figure it has to meet is 1 /m and it generates 2.12 1/m but i see gov MOT figure is 3.0 for turbo diesel cars before 2008


Passenger cars and light commercial vehicles – first used on or after 1 August 1979 and before 1 July 2008 3.0m


Have MOT got the wrong fail figure for this car?
I don't think it has a DPF
If they have it correct how do i get it passed the test
its done 144K miles just changes oil and filter and air filter (removed for one test )
I can find no air leaks in induction system though there is a ? over the CCV which seems to have free passage of air through it
I have run various cleaners through the fuel system and thrashed the engine for half a fuel tank , before last test i thrashed up and down A3 for an hour and they out it straight on tester but no change (2.5)
I have had the EGR valve out, it was not to dirty but cleaned and checked the diaphragm operation and seemed OK
Oil level lowered from full to half full
MAF ?
I have been to a couple of garage's and they advise to keep thrashing it! but i think that's not making the difference that's why I am wondering about the test bar i have to jump over! My daughter does not potter about and oil and filters changed frequently
It does chuck out big puff of BLACK smoke when revving to 4 K stationery but stops , just one puff
I cannot see any smoke when driving
Thanks for any advice to continue the life of this lovely car!
Gordon

[Crasher]

No DPF, that would be a BMM. I get the figure as 1.2m

[gordon123123]

OK Thanks , MOT man pointed it out on Plate as 1M any thoughts on id the CRANKCASE BREATHER OIL SEPARATOR MEMBRANE PCV (https://www.ebay.co.uk/itm/133728721920) needs a repair kit fitted? cant see inside the cover, seems to have a flow of air , uncontrolled after the MAF! cant work out how these separators
work and weather mine has disintegrated thus more oil in manifold thus more smoke = MOT Fail !

[Gazwould]

Could be alot of things from turbo exhaust seal to thermostat .

Try having a high mileage 2003 1.9 tdi Passat that has to blow below 0.60 !!

Now blowing a sweet 0.21 one acceration fast pass .

[philipharmes]

As Gazwould intimates, a healthy engine should have no trouble getting below 1.
All my old PD engine tests went through on a single fast pass.

But you do need to rag them well before the test.

The exhaust system can hold a lot of particulates that get trapped in nooks & crannies then blow out in one big clump as you said " It does chuck out big puff of BLACK smoke when revving to 4 K stationery but stops , just one puff "

You have to put your foot to the floor out on the road with the engine under load repeatedly, 2k up to 4k revs, until you see no smoke in your mirror.
Then take it straight in for a test.

Also does the engine reach operating temperature within 5 miles from cold.
A stuck coolant thermostat will increase particulates.

I don't see why you couldn't fit a catch can for the crankcase breather, but it really shouldn't need anything like that.

[Crasher]

A recirculating oil vapour condensation can is legal but unless the engine is totally knackered is going to make an unmeasurable difference to smoke emissions.