W164 OM642 Glow plug worry

[Shakeyxl]

Hi folks, recent purchase 2008 ML320, glow plug light stays on briefly, occasionally after starting, I have worryingly discovered among service docs an estimate from last year [ but no invoice] stating "glow plug 6 snapped in head require engineer specialist". I have a basic OBD2 app & only code it shows is P2138 - something different entirely. Seems to run OK, but have no frame of reference, all previous MB being petrol. All advice welcome. Thanks

 

[AndrewOl]

There are plenty diesel specialists out there that have the kit to get a snapped glow plug out as it is a common thing. Might be worth letting them have a look at it. Saying that one glow plug down is not the end of the world and if it has been starting ok in the recent cold snap then maybe save your money as something else is sure to come along to help empty your wallet!

 

[W1ghty]

Hi folks, recent purchase 2008 ML320, glow plug light stays on briefly, occasionally after starting, I have worryingly discovered among service docs an estimate from last year [ but no invoice] stating "glow plug 6 snapped in head require engineer specialist". I have a basic OBD2 app & only code it shows is P2138 - something different entirely. Seems to run OK, but have no frame of reference, all previous MB being petrol. All advice welcome. Thanks

The gp light staying on is briefly after start is normally a failed glow plug, or the damaged glow plug you refer to . May also be the gp relay module . Neither are a big problem .
Where do you live for recommendation to an MB specialist?
Or get the garage that sold the car to deal with it under warranty

 

[W1ghty]

Did you really join in 2007 and this is your first post ?

 

[BTB 500]

A failed plug will usually cause the light in the cluster to come on immediately after starting, then go off again a minute or so later. This is pretty common - the OM642 in my 2007 Vito had the first plug go at just 35k miles and they've been failing pretty regularly ever since! As a 6 cylinder engine it will still start easily with one (or even two) failed plugs. They can indeed shear off in the cylinder head when being removed.

A problem with the relay normally causes the light to come on and off randomly while driving, usually for 5-10 mins at a time. The issue here is that the relays aren't always available from MB.

Finally there's a special 225A 'mega fuse' for the glowplug circuit, which can blow.

I've needed both the relay and the fuse replacing, plus multiple plugs. Currently on 149k miles.

 

[zipdip]

I suppose you could have a look and see if the glow plug in number 6 is actually broken,I think your V6 looking at the engine from the front is at the back right hand side.

 

[DSM10000]

Hi folks, recent purchase 2008 ML320, glow plug light stays on briefly, occasionally after starting, I have worryingly discovered among service docs an estimate from last year [ but no invoice] stating "glow plug 6 snapped in head require engineer specialist". I have a basic OBD2 app & only code it shows is P2138 - something different entirely. Seems to run OK, but have no frame of reference, all previous MB being petrol. All advice welcome. Thanks

If the GP light showed when test driving the car (as it surely would of one is broken) why buy it?

 

[Shakeyxl]

{despite what torque pro says, Codes p2133 - p2138 on the OM642 =Glowplugs. P2138 should be the cylinder 6 glowplug, passenger side at the back of the engine [From another thread] Thanks for taking the time to help folks

 

[BTB 500]

{despite what torque pro says, Codes p2133 - p2138 on the OM642 =Glowplugs. P2138 should be the cylinder 6 glowplug, passenger side at the back of the engine [From another thread] Thanks for taking the time to help folks

Hopefully access won't be too bad on an ML ... that one is a bit tight on the Vito