OM642 Failed smoke test what to do first ?

tjamesbo

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1999 CLK430, 2007 VITO 3.0V6 , W124's (1994 320TE , 1993 220TE ) , 07 2.5 X-Type
Smoke Test Failure W639 3.0 V6 OM642 (220K mls ) Failed on Smoke test = ""emissions not tested " (excessive smoke ) so the current Plan
1 add some injector cleaner Fuchs is good but cant get it, same for forte ( few days delivery ) so wait or AN other STP / Wynns
2 Top Up with premium Fuel ( tanks just over half full at moment )
3 Take it on an italian tune up say a 20 minute thrashing holding a lower gear and giving it pedal to the floor 1
Try Cataclean or DPF cleaner now at the same time or later ??? will it mix ok with injector cleaner ? Both or just one ? if so which one
Maybe take it for a retest after that and get a reading then Pray
if it fails that then maybe Star test and here we go ££££££
1f631.png

of some concern is that I have the resistor swirl flap mod as mine stuck and therfore am worried that this might be an issue as previously passed all previous MOT's but its been driving fine and not aware of excessive smoke in my rear view mirror
The story begins ...................
 

Misterdog

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Oil change/filter air filter ?

Mileage ?
 

mioba

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Air filter changes on the OM642 apparently need a reset somewhere in the computer.

PCV

replace the orange seals to the turbo inlet
 

bladecrazy

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take for a good run then take back for the retest while shes nice and hot.
 

mersum1es

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It has DPF but still smokes? Either your dpf is gutted or then its so full it cannot capture everything which is pruducing in combustion. Check there is no boost leaks/splits on boost lines.
 
OP
T

tjamesbo

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Its on 220K now ,Air Filter relatively new done maybe 5-6K since changing , Oil just changed and Turbo Oil seal changed in March
When I start it from Cold and rev it it looks clean enough to me certainly not smokey . I then warmed it up and took it for a run with the wife following in her car I booted it, used kickdown , held onto gears, and mashed the pedal to the metal, she says she saw no smoke during any of that, so it cant be far out. I'm going to run some cataclean through it (its cheap enough ) then give it a long hard hot run then get it in for a retest hopefully straight after the run If it doesnt pass then its star diagnostic time and out with the wallet wide open
 

bladecrazy

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tesla model 3 performance /honda cd175/w123 300d gertrude.
I always test them the way the mot man does which is a couple of burst on the accelerator , go for a good run and make sure its atleast 80 degrees before you take it back , book a time and be there straight from the run.
 

Mr Filipov

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I would start by asking if the vehicle came out the factory with a DPF. if it didn’t and the MOT station assumes it does then that would be the problem.
 

M80

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As far as I'm aware all 639 V6 CDI's have a DPF.
 

Misterdog

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As far as I'm aware all 639 V6 CDI's have had a DPF.

Unless the previous owner only wished to max the performance/sod the environment and any future owners.
 


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