W211 om642 new glow plugs going faulty.

[boxer 01]

So over the last few months I have been getting the glow plug light staying on after start up and each time I have had to replace a glow plug as listed by my old foxwell scanner (altogether I replaced 3 over a period of 6 weeks)and this cured the faults. I had some old glow plugs so I used them as I needed to, with a view to ordering some new ones.
Eventually I ordered some new glow plugs and when the new beru ones came I fitted them and straight away cylinder 5 went open circuit which was worrying, so I replaced it and all was good, now No1 cylinder has gone open circuit, again I have replaced it and everything is fine.
My question is, is something causing my glow plugs to fail or have I got some dodgy new glow plugs, also I was having this issue before I fitted new glow plugs.
I'd like to mention, every time scanner has pointed to a glow plug it has indeed been the glow plug going open circuit.
I have heard of glow plug relays going faulty but I am not getting any fault codes for the relay. I would really like to hear the opinions of our om642 experts on here, thanks in advance.

 

[ALFAitalia]

Strange they are going open circuit.....they usually increase resistance as they fail. Standard resistance when fitted, between the tip of the glowplug and the head right next to it should be around 2 ohm....when they fail that usually jumps to around 40 to 60 ohms.
Failed one....

 

[herby thr cls]

So over the last few months I have been getting the glow plug light staying on after start up and each time I have had to replace a glow plug as listed by my old foxwell scanner (altogether I replaced 3 over a period of 6 weeks)and this cured the faults. I had some old glow plugs so I used them as I needed to, with a view to ordering some new ones.
Eventually I ordered some new glow plugs and when the new beru ones came I fitted them and straight away cylinder 5 went open circuit which was worrying, so I replaced it and all was good, now No1 cylinder has gone open circuit, again I have replaced it and everything is fine.
My question is, is something causing my glow plugs to fail or have I got some dodgy new glow plugs, also I was having this issue before I fitted new glow plugs.
I'd like to mention, every time scanner has pointed to a glow plug it has indeed been the glow plug going open circuit.
I have heard of glow plug relays going faulty but I am not getting any fault codes for the relay. I would really like to hear the opinions of our om642 experts on here, thanks in advance.

You say that you had this issue before you fitted the new plugs, therefore i would be looking at the glow plug relay, sounds like the timer inside the relay is stuck on and burning the glow plug out due to it not switching off

 

[Smart320]

Also would change the relay before doing anything else

 

[BTB 500]

The glowplug circuit is fused at 225 Amps so if the relay was stuck and all six plugs were permanently on I suspect there would be other problems!

Open circuit might suggest a connector/wiring problem that is 'fixed' (temporarily) when you change the plug. Have you tested the plugs you've removed?

 

[W1ghty]

Are there two sorts of glow plugs on our engine ?? Are some 4.5v and others 12v .
Do you now have different makes of plug in the engine , not sure if that would make a difference.
If you have never changed the gp relay , they don’t last forever .

 

[boxer 01]

Sorry for the late reply but I had another issue with the car after changing the glow plug, turned out it was the exhaust back pressure sensor making the car do all sorts of weird stuff. Yes I did test the plugs after removal and they were open circuit, I did think of the relay being at fault and deep down still think it might be the culprit.
I have all beru in but a couple of old good ones and everything seems to be good at the moment, I did the relay about 3 years back but if they keep burning out I will be in the market for a new relay.

 

[m80]

As Whighty, be sure the voltage of the glow plugs match the output of the relay.

 

[boxer 01]

Glow plugs are 4.4v beru and the correct ones for my engine. The relay is supposed to be the correct one and it's been in for a while now, I think the best bet is to monitor the situation and see if the fault persists, if it does then go for a new relay.

 

[W1ghty]

Glow plugs are 4.4v beru and the correct ones for my engine. The relay is supposed to be the correct one and it's been in for a while now, I think the best bet is to monitor the situation and see if the fault persists, if it does then go for a new relay.

What make relay is it ?

 

[m80]

You could measure the voltage output of the relay when cold.
Something is blowing the glow plugs, or they are a bad batch.

 

[boxer 01]

What make relay is it ?

Beru relay