Emissions failure - is it all over now?

[DMitch16]

Well, it's finally happened and my lemon is blowing 2.26 on the MOT smoke test after passing last year with a 0.43 average so under the 0.50 plate figure. I did notice some black smoke from the exhaust during the test runs which is unusual as I have a DPF but this may suggest other combustion issues or boost circuit leaks.

This is after I have serviced the car, new correct spec oil, new oil, air and fuel filters although I went away after this and the car was left standing for a week then driven only 14 miles to work then 4 miles to the MOT. Might be that the cat was not hot enough but I suspect other issues as there is an oil leak from the crankcase vent pipe which used to be bone dry.

The only thing I did not do this year was to run a cleaner (normally Liqui Moly Diesel Purge) through the tank before the MOT and use a tank of V Power premium diesel leading up to it. This is in progress now before the retest next week but is there anything else I can check on the car or with VCDS that could indicate a combustion issue instead. I will be cleaning the EGR valve and intake manifold and checking their operation at the weekend and also inspecting the boost pipe seals for leaks.

Everything else on the car is still spot on and working, drives beautifully and even my Mercedes loving father was impressed with the drive the other week when I drove him and my mother to an anniversary meal so he could drink for once.

Any help appreciated, apart from 'scrap it' of course which is probably going to happen sooner or later.

[Gazwould]

The B6 might not have a special fuse that the B5 has !

What Merc does Pops have ?

[DMitch16]

The B6 might not have a special fuse that the B5 has !

What Merc does Pops have ?

Pops has a 2005 E320 Cdi, the one with the straight 6, arguably to some their best diesel engine ever. Fully loaded, leather, heated and cooled everything, panoramic roof, sat Nav head unit and 0 to 60 in 7 something. He just won't hand it down!

Special fuse Gaz?

[Gazwould]

Oh yeah the W211's are lovely just the air suspension can be a pain .

Pulled the reversing light/ cruise control fuse and it drives as flat as a pancake - cuts the fueling right down !

0.05 !!

[DMitch16]

Oh yeah the W211's are lovely just the air suspension can be a pain .

Pulled the reversing light/ cruise control fuse and it drives as flat as a pancake - cuts the fueling right down !

0.05 !!

Retest blew 0.05 and no fuses removed! Just needed a cleaner, V Power and a new EGR valve, old one was original part with 225k of service. Probably not closing either fast enough or completely ������

[Gazwould]

Can't think but a cat helps catch some !?