Struggling Pre-heater

[Shakey]

I have a '94 4-runner, 3.0 TD, which is without doubt the most satisfying vehicle I have owned. However it's not without it's niggles (makes life interesting though eh?). This particular niggle concerns the diesel pre-heater which, when cold, sometimes refuses to come on at the turn of the ignition. It sometimes happens when warm and then cranking has no effect. I'm guessing it is linked somehow to a fuel feed solenoid of some sort which is also not switching on when I turn on the ignition. When this occurs, I have to switch the ignition off and back on a number of times before the glow lamp on the dash comes on (and then goes out as it should). After that all is sweetness and light.
I'm wondering if it is a loose contact on the ignition circuit or more likely to be a dodgy fuel heater/glow plug solenoid.

Anyone come across this before?

[foggy]

If you look in the stickey topic at the top of this page,you will find a diagram
of the heater circuit-there is a circuit that affects both the heater and the
fuel solenoid from the ignition switch.Best of luck!

[Shakey]

cheers Foggy!