C250 Turbodiesel Heater Plugs

[Guy Greenwell]

Just a quickie for infirmation.
I had a heater plug fail the other day and shopped around for prices which were as follows:-
Halfords, First price £28,after showing total disbelief & saying I wanted 1 and not a set, was quoted £24 each.
Euro car parts, internet price, just over £12.-- Better.
Partco £6.77+vat. for NGK plugs.
Hope this helps everyone.
Regards, Guy.

 

[nicky]

Just a quickie for infirmation.
I had a heater plug fail the other day and shopped around for prices which were as follows:-
Halfords, First price £28,after showing total disbelief & saying I wanted 1 and not a set, was quoted £24 each.
Euro car parts, internet price, just over £12.-- Better.
Partco £6.77+vat. for NGK plugs.
Hope this helps everyone.
Regards, Guy.

it does pay to shop about,,,have you fitted them yet????

 

[Guy Greenwell]

Heater plugs

Hi Nicky,
I fitted them the othed day. No problem really as follows:-
1. Remove air inlet pipe from across top of engine (2 Jubilee clips).
2. Remove inlet manifold, by undoing 10 spline drive screws fixing it to the cylinder head and 2, 10 mm bolts fixing it to a steady bracket.
3.Pull off the electrical connection from the plugs.
4. Unscrew the faulty heater plugs and replace.
Reassembly is a reversal of dismantling.
Faulty plugs can be identified once disconnected by using a multimeter on the ohms setting and putting one lead to the heater plug terminal and the other lead to the cylinder head.good plugs will move the pointer to the otherend of the scale or show virtually 0 ohms resistance, wheras a faulty plug will not cause the pointer to move or show infinite resistance on a digital meter.
Cheers, Guy.

 

[steve kane]

Hello everyone, well we have an older P Reg C250 Diesel (non Turbo) which has been an excellent starter untill now, the GloPlug warning light comes on for what has always seemed quite a short time, just a few seconds, goes off and we try to start, the engine fires on perhaps one cylinder and cuts out, then its a real effort to start, Im assuming its Glo Plugs/cold weather but I also see in the Haynes Manual (what a crappy offering that one is!) that the timing of the GloPlugs is determined by a coolant temp sensor, and oddly we have not had any warning of GloPlug problems indicated by the warning light coming on after starting, could it be the sensor preventing the gloplugs getting really warmed up in the colder weather? also Im hopeing that my plugs are easier to remove than with the newer engines, I think they are located on the side of the Head under the Inlet Manifold, does anyone know what these are like to change and do I have to remove the Manifold?
all advice gratefully recieved,
Steve.

 

[steve kane]

C250D Starting Update

Well just to confuse things I popped out this morning and the car started first time (instantly) despite a heavy frost on the car and the heater plug lamp only showing for perhaps 4 seconds, so I guess from my prev diesel experiance that the heater plugs are funtioning, I wonder if its an intermittant fault, dodgey connection on some electronic gizmo, any ideas where I could look?
Steve.

 

[Parrot of Doom]

Could be a fault with the glow plug relay, perhaps not allowing enough current to flow for long enough that the tips of the plugs get hot?

 

[steve kane]

Perhaps Dodgey Fuel??

Well this morning my wife said, "we only started haveing this problem since filling up last week" which is quite true, yesterday we had great difficulty starting at midday when it was not cold at all, and whilst out and about we filled up again at a different garage, this morning, despite a heavy coating of frost on the car she fired up instantly, now it could be an intermitant GloPlug/Relay fault but we live in hope and Im keeping my fingers crossed and will report back,
Steve.

 

[Parrot of Doom]

Steve, have you considered an air leak? The plastic pipes around the fuel filter and their O-rings are a common fault. Look for air bubbles before you start it in the morning. Usually obvious when parking on an incline, facing up the hill.