OM642 E320CDI 2006 facelift - white smoke from the exhaust and MOT

Stocho

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Hi,

A car (OM642 E320CDI 2006) has not been driven for months and had a seized alternator that was fixed yesterday. (2006 E320CDI not used for months, when started serpentine belt smoked and snapped, alternator appears to be seized | Engine )

The garage initially themselves offered to do MOT as well - I explained to them that the only hesitation I had about them doing MOT is that the car has not ben driven much recently and if emissions are tested not on hot engine it might fail but they said they would warm it up. So we agreed that they would do it. But they then phoned and said that they do not have time to actually do it. I asked whether there was anything that suggested to them it might not pass and they said white smoke from the exhaust. They said may be driving it at speed would help but perhaps it is a wrong mixture in the engine and they would not want to fail it on that. When I collected the car the engine was in fact warm - so perhaps the real reason they did not want to do MOT because they did not want to fail it.

The MOT on the car has run out (could not be MOTed in time due to alternator) . So the only way for me to drive it long distance (especially given the perverse judgement in Pumbien v Vines) before MOT is to book MOT somewhere far away (but then lockdown rules might kick in as well).

Is there some additive I can add to the fuel tank to fix the issue (something like DIPETANE DP005 100% Hydro-crabon Fuel Treatment: Amazon.co.uk: Car & Motorbike) ? How long do I have to drive it for and at what speed to have a chance of resolving the problem? I do plan to use Forte Injectors cleaners and their other products but for MOT I need something that will improve emissions immediately rather than once it is used up...

Also under the new regime is emission test failure classed as "Dangerous" meaning that I would not be able to drive the car at all - even back home or for repairs?

Another curiosity question I have is: I also have another OM642 E320CDI 2007. The 2006 car is not allowed into London ultra low emissions zone while 2007 car is. Don't they have exactly the same engine? Why would there be a difference?
 

Gazwould

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For less soot .

Boost the Cetane number of the derv with an actual Cetane booster ingredient..
 
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Stocho

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For less soot .

Boost the Cetane number of the derv with an actual Cetane booster ingredient..

Thanks a lot!

So something like this (99% pure 2-Ethyl-Hexyl Nitrate Cetane Booster) ?

Should I stick to the recommended ratio of 500:1 or go even higher?

Can I also use Forte Diesel Emission Reducer at the same time?

I also heard about "Italian tune-up". To do this do I have to manually change gears to keep it at higher revs than auto would do? At what speed, what revs and for how long should I drive it for this "Italian tune up" to work?
 

Petrol Pete

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This is a conundrum, as I understand it you do not have to book your car into the nearest MOT station to drive it without an MOT (even before covid) , but to book it in Aberdeen if you lived in Manchester is a bit of a no no.

I am not quite sure how this works and who decides but I had a similar 'problem' with my van that was out of MOT . I booked it into my mate's MOT centre a mile away and he diverted me to an HGV/coach company he deals with about 20 miles away, he said it best I give the old van a good kickin' (Italian tune up) and a few stomps on the brake pedal as it had been stood for a while.

I asked him if driving this distance was allowed, and his reply was 'just about , but don't take the P and start driving around , go directly to the test station' . You will need way more than 20 miles to get a regen done (if that is what is required) and no amount of additives in the fuel are going to help unless that fuel is burnt by the engine...which means using at least a tankful. :eek:
 
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Stocho

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This is a conundrum, as I understand it you do not have to book your car into the nearest MOT station to drive it without an MOT (even before covid) , but to book it in Aberdeen if you lived in Manchester is a bit of a no no.

I am not quite sure how this works and who decides but I had a similar 'problem' with my van that was out of MOT . I booked it into my mate's MOT centre a mile away and he diverted me to an HGV/coach company he deals with about 20 miles away, he said it best I give the old van a good kickin' (Italian tune up) and a few stomps on the brake pedal as it had been stood for a while.

I asked him if driving this distance was allowed, and his reply was 'just about , but don't take the P and start driving around , go directly to the test station' . You will need way more than 20 miles to get a regen done (if that is what is required) and no amount of additives in the fuel are going to help unless that fuel is burnt by the engine...which means using at least a tankful. :eek:


But I thought Cetane Booster should work as soon as it mixes well in the tank and starts flowing to the engine. Doesn't it improve combustion and improve white smoke immediately or it also works by cleaning the engine rather than purely through lowering ignition temperature?


That Forte product is marketed as "specifically formulated to rapidly reduce exhaust emissions and help vehicles pass the new emissions test" so was hoping that it is more rapid than the usual Forte products that have good reputation but do have to substantially go through the engine to work... Perhaps will call Forte on Monday to inquire...
 
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Stocho

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Had advice from Forte that their product and cetane booster can be used together. They also advised that the more of their product runs through the engine and advised to drive at least 50miles before MOT.

I used both of the above products and booked MOT in a place about 20 miles away (not 50 as Forte suggested). I also tried driving with manual gear selection to keep engine round 3k. It passed!!!

But yet another problem with the car appeared on the way to MOT - windscreen / saloon heat blower.... Luckily it is not part of MOT test. So yet another thread about problems with this car... W211 E320 CDI 2006 facelift Windscreen Blower not working | Electronics and Audio

But now it does have an MOT now!
 

TeddyRuxpin

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With regards to the 2007 OM642 E-class that is ULEZ compliant - perhaps it was once registered as a taxi? Because no E-class pre-2012/2013 E320/E350 (very very late pre-facelift 212 and all facelift E350 W212s) should really be ULEZ compliant as they aren't Euro 6 (no ad-blue).

My 2009 W212 E350 currently shows up as ULEZ compliant but another 2010 in the family does not, and the only thing I can think of is that it was once used as a chauffeur car so perhaps it was registered as a London taxi at one point... taxi's have an extra ~18 months to comply with Euro 6, I believe.

Could also just be an anomaly in the database that changes status at any moment.

Glad your car passed and is up and running!
 

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