Is it ok to run without glow plug relay?

[W203Wanderer]

My glow plug light stays on for a minute with my E220 w211 2006/07. It starts fine, I’ve started it in minus 4 fine. I’ve changed all the plugs and the light remains. If it’s a relay it’s going to cost me a few hundred. Unless anyone knows what else I could check? Is there any problem with leaving it as is? Will it cause damage over the years? Thanks

 

[W203Wanderer]

When I say a minute I mean after starting

 

[mersum1es]

Your glow plugs will stuck, they will snap when someone wants change them later.

 

[alecmascot]

My glow plug light stays on for a minute with my E220 w211 2006/07. It starts fine, I’ve started it in minus 4 fine. I’ve changed all the plugs and the light remains. If it’s a relay it’s going to cost me a few hundred. Unless anyone knows what else I could check? Is there any problem with leaving it as is? Will it cause damage over the years? Thanks

Used one for £30 on ebay (from Lithuania)

 

[W203Wanderer]

Used one for £30 on ebay (from Lithuania)

Hi please link me, would it fit my 2006 facelift? Thank you.

 

[W203Wanderer]

Hi please link me, would it fit my 2006 facelift? Thank you.

I’ve taken mine out, it looks similar to this Glow Plug Control Unit Relay Fits W211 S204 W204 S211 C E 6461532579 A6461532579 | eBay

 

[alecmascot]

Hi please link me, would it fit my 2006 facelift? Thank you.

mercedes om646 glow plug relay for sale | eBay

Find great deals on eBay for mercedes om646 glow plug relay. Shop with confidence.

www.ebay.co.uk

 

[DSM10000]

Your glow plugs will stuck, they will snap when someone wants change them later.

The OP has just changed the glow plugs.

What are you suggesting?

 

[mersum1es]

The OP has just changed the glow plugs.

What are you suggesting?

If plugs are not used, they will stuck. Probably something to do how they not expanding when they are cold and then carbon can penetrate on tight gap/acuumulates on plug tip better than hot plug. I am not 100% sure but thats one explanation which I buy... Truth is that used plugs will stuck almost always if they are not changed pretty quickly after they are gone bad.

 

[renault12ts]

If plugs are not used, they will stuck. Probably something to do how they not expanding when they are cold and then carbon can penetrate on tight gap/acuumulates on plug tip better than hot plug. I am not 100% sure but thats one explanation which I buy... Truth is that used plugs will stuck almost always if they are not changed pretty quickly after they are gone bad.

*stick*

 

[E55BOF]

As I read it, the OP's problem is that the glow plugs are staying on, and hence hot, too long, not that they are not coming on at all.

 

[DSM10000]

If plugs are not used, they will stuck. Probably something to do how they not expanding when they are cold and then carbon can penetrate on tight gap/acuumulates on plug tip better than hot plug. I am not 100% sure but thats one explanation which I buy... Truth is that used plugs will stuck almost always if they are not changed pretty quickly after they are gone bad.

But the OP has clearly stated that they have changed the glow plugs hence they didn't get stuck.

 

[mersum1es]

But the OP has clearly stated that they have changed the glow plugs hence they didn't get stuck.

Yes but as I understood glow plug realy is not now working? = plugs not working. Same result?

 

[E55BOF]

The glow plugs are working, but the glow plug light stays on. Terry Gates had the same thing on his old diesel W163 that I had as a courtesy car once, and he never worried about it, if that helps.

 

[DSM10000]

Yes but as I understood glow plug realy is not now working? = plugs not working. Same result?

No. You said plugs will break on removal, my point is that the OP has removed (or has had someone do so) the plugs and they didn't break.

 

[BTB 500]

The heat from the plug element being on for 5 secs or so is surely negligible compared to it being exposed to combustion temperatures in the cylinder for hours at a time when the engine is running??

 

[mersum1es]

No. You said plugs will break on removal, my point is that the OP has removed (or has had someone do so) the plugs and they didn't break.

OK, you didn't get what I am trying to say so let's forget it, probably I lost in translation here...

 

[mersum1es]

The heat from the plug element being on for 5 secs or so is surely negligible compared to it being exposed to combustion temperatures in the cylinder for hours at a time when the engine is running??

Of course, that theory applies only few seconds. Dull plugs just will eventually jam, for some reason. Its not happening in days or week, but after half year it probaly will snap because tip is not moving any more.

 

[BTB 500]

OK, interesting. I've had dead plug(s) for most of the time I've had my OM642 ... I get them replaced periodically. I think the relay has gone now though as cold starts are suddenly taking a while ... it's on the 'to do' list!

 

[W203Wanderer]

OK, interesting. I've had dead plug(s) for most of the time I've had my OM642 ... I get them replaced periodically. I think the relay has gone now though as cold starts are suddenly taking a while ... it's on the 'to do' list!

Note, I’ve looked and relays are anywhere from 120-260. I’m going to order one off aliexpress that’s OEM quality apparently for 25/£40 I will let you know how it goes.