Mercedes-Benz E-Class W210 - Checking glowplugs

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Fri 11 Jan 2013 16:03
Mercedes-Benz E-Class W210 - Checking glowplugs - Alanovich

I'm thinking about looking at a 2001 Merc E320CDi estate with a view to purchasing. HJ's advice, in capital letters, is to CHECK THE GLOWPLUGS.

My question is, how does one check a glowplug, and what is one looking for? I'll look for evidence of them having been changed in the car's invoice history, but on a physical level how on Earth would one go about doing this on a used car forecourt?

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Fri 11 Jan 2013 17:31
Mercedes-Benz E-Class W210 - Checking glowplugs - Collos25

Its very difficult but I think what HJ means to see if they can be removed and they are all in one piece, these heads are renown for for having ceased glowplugs and it is very expensive to replace a broken glowplug.

To physically check them first remove them one a time apply 12v and you should see them glow red.

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Fri 11 Jan 2013 18:14
Mercedes-Benz E-Class W210 - Checking glowplugs - elekie&a/c doctor

It is not critical for the glow plugs to work on this model.As with most common rail diesel engines ,the cold starting is looked after by the electronics of the engine control system.The glow plugs can be tested without removing them from the engine by doing a current drain on each from the glow plug control relay.I would be more concerned if there is any build up of sludge around the injectors which could indicate excess blow by or worn sealing rings or a possible cracked injector.You need to remove the engine top plastic covers to check this.hth

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Mon 14 Jan 2013 12:59
Mercedes-Benz E-Class W210 - Checking glowplugs - Alanovich

Would a 2001 (51 reg) W210 have a common rail diesel engine? Didn't think they were that old.

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Mon 14 Jan 2013 13:22
Mercedes-Benz E-Class W210 - Checking glowplugs - Peter.N.

You can check them in situ with a meter, disconnect the leads one at a time and measure the resistance to earth, it should be around one ohm or less, if you get no reading at al its dud.

I think by that time they were common rail but might be worth checking, if it is the glow plugs are not essential unles you live in Siberia.

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Mon 14 Jan 2013 14:51
Mercedes-Benz E-Class W210 - Checking glowplugs - gordonbennet

I used to keep an old Lucas dashboard ammeter +-30amp for such jobs, invaluable. Jerry wire to each individual plug in situ or out, usually around 20 amps draw for a good plug, soon see if one or more was dying.

Someone borrowed it and never seen again, another lesson learned the hard way.

Edited by gordonbennet on 14/01/2013 at 14:51

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Mon 14 Jan 2013 15:39
Mercedes-Benz E-Class W210 - Checking glowplugs - elekie&a/c doctor

Most Merc diesel engines are common rail from around 1998.I think you will find the clue is in the title;Common (rail) Diesel Injection.hth

Edited by elekie&a/c doctor on 14/01/2013 at 15:40

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