Glowplugs & CDi engines - a warning

[Jukie]

If you have need to remove a glowplug from a CDi engine, be careful. They are rather fragile and thinner than in previous engines, 10mm as opposed to 12mm. No matter how careful you are when trying to remove them, it is quite possible to break them, leaving them stuck in situ.

The only recourse, it seems, is to remove the head and drill them out. Mercedes know it's a problem (local stealer admitted last week they're averaging 2 a week) but will not cover it under warranty, unless the plug failure occurs after an unreasonably short time.

 

[Brian WH]

If you have need to remove a glowplug from a CDi engine, be careful. They are rather fragile and thinner than in previous engines, 10mm as opposed to 12mm. No matter how careful you are when trying to remove them, it is quite possible to break them, leaving them stuck in situ.

The only recourse, it seems, is to remove the head and drill them out. Mercedes know it's a problem (local stealer admitted last week they're averaging 2 a week) but will not cover it under warranty, unless the plug failure occurs after an unreasonably short time.

Don't worry only the Dealer will be trying to take them out, he breaks he replaces at his expense. But thanks for the info.

 

[Dieselman]

Get the engine hot first as this will expand the aluminium more than the steel glow plug and will reduce the grip on the plug.

 

[IanT]

I believe my new (to me) 2001 E220 CDI may have a dead plug. It's done 161k miles and is in surprisingly good shape (that being the reason I bought it).

Sometimes (particularly when the engine is very cold) the glowplug light comes on as normal, for about 1 second maximum and then goes out, but returns again once the engine is started for about 3-5 minutes. On my previous C250 this indicated a blown plug but was accompanied by nasty rough idling until the engine was warm, but on this car it doesn't appear to be a problem.

I'll have to have a look at the plugs with a multimeter and see if there are any that are open circuit or significantly different to the rest. Are they all easy to get at on this engine? I remember that on the 5 cyl engine the plugs in no1 and no2 were relatively easy to remove but the rest were under the inlet tract.

Oddly the owners manual doesn't seem to cover fault indications on the glowplug dash telltale and the dash display shows 'no malfunction' when called up via the steering wheel controls. Am I barking up the wrong tree?

Cheers, Ian.

 

[25 Ttriumph]

glow plug

Was the light staying on accompanied by small smoke emmission on start up?
Has a change of glow plugs solved the problem?
Keith

 

[Dieselman]

Direct injection engines don't really need glowplugs so you shouldn't notice any rough running or smoke.

The light is indicating a plug failure so really it should be done for peace of mind in case the temps get down to -15 or so.