no 12v feed to glow plugs 2.2td JEOE G8T engine

[P,G,Spaven]

Hi,  the EGR computer has a feed and the dash display glow plug sign comes on (only for approx 3secs though)and then the ok light comes up but at no time are the glow plugs getting 12v! I'm stuck! Is the EGR fed with a timed relay? I can't even find the NAGARES pre heating unit! It says in the vaults that it's located on the pump?I'm just outside Scarborough and don't have a clip. Can anyone help please?

[P,G,Spaven]

Just thought, is the NAGARES  pre heating unit that's mentioned as being on the pump a pre heat for the diesel and not as I first thought part of the glow plug pre heat circuit?

[roy4matra]

Hi,  the EGR computer has a feed and the dash display glow plug sign comes on (only for approx 3secs though)and then the ok light comes up but at no time are the glow plugs getting 12v! I'm stuck! Is the EGR fed with a timed relay? I can't even find the NAGARES pre heating unit! It says in the vaults that it's located on the pump?I'm just outside Scarborough and don't have a clip. Can anyone help please?

Hello PG,

The very first thing is to check the glow plug resistances.  Do you have a good Ohmmeter?  You put the one probe to the electrical connection and the other to earth and you should get around 1 ohm (say 0.8 to 1.1) for each plug.  If you get a very high resistance or open circuit the plug has burnt out.  It is possible if they haven't been checked or replaced in a long while, they have all failed.  I have seen this before.

The plugs are fed from a relay contained in the injection computer which time controls the plugs depending on temperature.  So if the engine is cold, you will get the maximum time whilst if hot they may not be operated very long.  So if yours are not operating at all, it could be, for instance, an injection computer fault, a temperature sensor at fault or a wiring fault, and there is deliberately no operation.  So I would check the plugs first and the wiring connections second.

(amended as I realised this was a G8T not a G9T engine)

Roy

[BrianM]

I still think it is because you are bye-passing the immo. With the immo light on i'm sure the ecu isn't giving you the feed even though it is showing on the dash. Roy, the car starts if he puts power to the plugs direct. I suggested a timed relay from an old pug or rover to get around it.