Please what is this and whats it for/do etc....or as I suspect not doing...

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Smoke colour?
 
if you park up with engine running for say 15-20mins

in my case...sat waiting for the Kids to come out of school watch TV in it with engine on so not to flatten battery

As an aside ... being parked up with the engine running has been illegal in the UK for a while now, and if you do it regularly near a school there's a fair chance someone will report it. Particularly a older diesel that's pushing out smoke!
 
It should also take a lot longer than 15-20 mins with the radio on to flatten a properly charged battery in good condition.
 
White ish blue...defo not black.....
Have a useful doc on diesel smoke that I use for diagnosis.

Blue smoke:

Blue smoke is caused by engine lubricating oil burning. The oil can enter the combustion chamber from several sources including:

· Worn valve guides, or seals
· Cylinder &/or piston ring wear
· Cylinder glaze
· Piston ring sticking
· Incorrect grade of oil .. too thin and getting past rings, or valves guides
· Fuel dilution of the oil, making it too thin.

Blue smoke is often evident at cold start, which can reflect reduced oil control due to carbon fouling deposits around the piston rings and/or cylinder glaze. Blue smoke should not be evident at any stage.
An engine may burn oil without the evidence of blue smoke, because good compression burns oil quite cleanly, however, it is not acceptable for any new engine, or engine in good internal condition to burn large amounts of lubricating oil.

White smoke:

White smoke is caused by raw, un-burnt fuel passing into the exhaust stream. Common causes include:
· Incorrect fuel injection timing
· Defective fuel injectors
· Low cylinder compression

Low cylinder compression may be caused by leaking valves, sticking piston rings, ring wear, cylinder wear, or cylinder glaze. When white smoke occurs at cold start and then disappears as the engine warms up, the most common causes are fouling deposits around piston rings and/or cylinder glazing.
Continuous evidence of white smoke indicates a mechanical defect, or incorrect fuel timing.
 
On the battery and engine running etc....as the car is "new to me" and the battery went flat in the garage while working on it, I just did not want to get stranded...once my confidence in the car has built up I agree....should be able to sit with radio on for 1/2 or so no problem....am also Disabled so hate getting stranded and the wife is away on Business...thats the only reason I sat with the engine on and noticed the issue.....it has a new battery now anyway....my point is.....it should not do it....i.e. if stuck in traffic jam on motorway it would smoke too after 15 or so mins...unless thats illegal and you have to turn your engine off then too.....:) ?
 
Have a useful doc on diesel smoke that I use for diagnosis.

Blue smoke:

Blue smoke is caused by engine lubricating oil burning. The oil can enter the combustion chamber from several sources including:

· Worn valve guides, or seals
· Cylinder &/or piston ring wear
· Cylinder glaze
· Piston ring sticking
· Incorrect grade of oil .. too thin and getting past rings, or valves guides
· Fuel dilution of the oil, making it too thin.

Blue smoke is often evident at cold start, which can reflect reduced oil control due to carbon fouling deposits around the piston rings and/or cylinder glaze. Blue smoke should not be evident at any stage.
An engine may burn oil without the evidence of blue smoke, because good compression burns oil quite cleanly, however, it is not acceptable for any new engine, or engine in good internal condition to burn large amounts of lubricating oil.

White smoke:

White smoke is caused by raw, un-burnt fuel passing into the exhaust stream. Common causes include:
· Incorrect fuel injection timing
· Defective fuel injectors
· Low cylinder compression

Low cylinder compression may be caused by leaking valves, sticking piston rings, ring wear, cylinder wear, or cylinder glaze. When white smoke occurs at cold start and then disappears as the engine warms up, the most common causes are fouling deposits around piston rings and/or cylinder glazing.
Continuous evidence of white smoke indicates a mechanical defect, or incorrect fuel timing.

It looks like I'm going to book it in with my local Diesel specialest....get a full diag....
Another question....on a 57 plate will it have a DPF or not??
 
Re DPF unlikely but they were an optional extra around that time
 
On the battery and engine running etc....as the car is "new to me" and the battery went flat in the garage while working on it, I just did not want to get stranded...once my confidence in the car has built up I agree....should be able to sit with radio on for 1/2 or so no problem....am also Disabled so hate getting stranded and the wife is away on Business...thats the only reason I sat with the engine on and noticed the issue.....it has a new battery now anyway....my point is.....it should not do it....i.e. if stuck in traffic jam on motorway it would smoke too after 15 or so mins...unless thats illegal and you have to turn your engine off then too.....:) ?

1PACK DIGITAL DC AUTO BATTERY VOLTAGE METER Voltmeter Car Lighter Socket Plug-in | eBay

With oneof these in the ciggy socket you can monitor the voltage and be warned of it dropping, if the voltage drops to perhaps 12.3 volts start the engine.
Also useful to compare battery voltage on cold morning and 'possible' forewarning of it going u/s.

I would compare actual readout to real readout with a dvm though, not all are accurate in my experience, but if you are aware of the error no problem.

I guess you're already aware of the residual heat function (if yours has it). Can keep you warm for a further 30mins when sat waiting?
 
All very useful.....but not realy helping me on it smoking on long idle....it will clearly fail MOT as they leave the engine running for Smog test :( I've seen that there are RED improved intake rubber seals for the Turbo intake and the Oil Catch connection....mine are orange and one of the 1st things I did was remove and clean them as was weaping....also believe there is an "improved" catch tank thing....i.e. these:-
s-l1600.jpg

s-l1600.jpg


Could this simply be seaping and burning during idle but not noticable when driving??
 
The top looks like your pcv, and could cause smoking.
The orange seals, 1 for the heater, the 1 for the turbo spigot has been upgraded a couple of times I think. That wouldn't be responsible for the smoking but as said earlier might be leaking onto the inlet port motor, that isn't there any longer in your case.

Be careful as upgraded 'turbo' seals don't always fit well into the original plastic air intake duct. You might break the ends off while tightening.
 
The top looks like your pcv, and could cause smoking.
The orange seals, 1 for the heater, the 1 for the turbo spigot has been upgraded a couple of times I think. That wouldn't be responsible for the smoking but as said earlier might be leaking onto the inlet port motor, that isn't there any longer in your case.

Be careful as upgraded 'turbo' seals don't always fit well into the original plastic air intake duct. You might break the ends off while tightening.

One is the "T" inlet to Turbo Seal and the other is the OIL Catch tank feed...not sure where you got heater from??
You can see them both here....large is Turbo intake and the smaller is the "fumes" from oil into intake one....
Both known to drip oil, so if they can drip oil...and they are on the intake side to the turbo the oil can be sucked into and burnt in the engine......thats my thoughts anyway....same as Jeep motor apparently.
 

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The small one is for the heater to sit into, measuring approx 18 ohms if memory serves.
The larger can have an oil catch added I've read, but it is your air intake into turbo. The oil from the pcv will be what leaks from it onto the motor below, when fitted.

I used to clean the orange spigot seal with white spirit and appply a silicon bead inside and outside at re assembly.
To check for leaks I would wipe a white tissue around the underside.
I didn't have problems after applying the silicon.
But since I've read that the intake flaps can disintigrate into the engine I can see advantage to removing those and blanking.

After that you only need concern yourself with the crank seal and oil cooler seals on the 642.
Nice engines though.
 
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Still confused....the orange bottom left with the 2 wire plug is a heater??? i thought is was a sensor of some type?

Reading here on another site its part of the standard oil fume recycle gubbins....but its not very good at what its supposed to do and oil not just fumes get through....
Someone added their own LARGER catch tank due to oil being sucked through and into the turbo......
its on a GL but from what I can tell its the same Engine....

GL350 oil catch can install - MBWorld.org Forums
 
After that you only need concern yourself with the crank seal and oil cooler seals on the 642.

Or the manifold liner delaminating and wiping out the turbo :(
 
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Quick search says its:-
Genuine Mercedes-Benz OM642 Engine Air Intake Sensor A6420160330
Not heater?
 
I only know what I think I know, so I'll leave this to those that know better than I and I know that there are plenty of those in the know.


I think.
 
Eh I don't....................................................know LOL
Its defo crank breath being recycled into intake.....would have thought as the oil fumes can only be created when warm there would be know need for a heater.....anyway gonna replace those and even maybe fit a catch tank later....main thing is sorting this idle smoke out....other searchs say possible injectors....leaking so does not show on run but could when stopped....but then to me that would produce black smoke not blue/gray....altho been said it can reach the oil....thus oil level will rise then that gets burned off.......did oil change and it was bit runny and smelly too....so maybe that....also not 100% as to if it has DPF!
Why I may just book it in....my thoughts being and hoping it can't be anything to major as running great and using it daily at mo ....just make sure i turn off when I stop for ages....it just knowing theres an issue and like I say...its not going to pass next MOT for sure......just bugging me now...
 
I noticed this when changing the turbo seal and PVC (I'll post pics later showing deformed seal)

Just cut up the old PVC. Copper pipe inside with 2 electrical connections. Assume its a heater.
And I assume it's a ridiculous emissions device that heats the crank case emissions when the engine is cold.
 

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