Revs Hunting when cold ?

Hi,
Got a problem that is getting worse as the temp is dropping..
My P38 RV8 (1997) is Hunting when cold and also the revs are so low it's barely registering on the tacho.
The colder weather has dropped the revs to this point it was ok at around maybe 300 while cold before.
Typical day right now:
Start the car, it hunts for a few minutes while I scrape the windows. moving between 150 and 500 revs,
Drive off and the revs are dropping to almost nothing at junctions etc.
Once warmed abit the revs get alittle higher until once fully warm the engine ticks over fine at 450 revs and no hunting to speak of.
If you then stop and restart the engine while warm, it will hunt for a minute between 200 and 600 until you drive off, after that its fine again.

Is a sensor or the stepper misbehaving ?

Thanks,
Stu

Possible Idle Control Valve (Stepper Motor) or the Engine Thermotime switch (ECU Engine Temp Sensor) which controls the Stepper Motor via the ECU....

Thanks for the info, that makes perfect sense... Where is the best place to find such a sensor ?
Would Europarts have this over the counter or do I need to go to onine specialist supplier ?

Thanks..

Stu

Most likely or any local motor factors like Unity or Camberly should have one....

or you could try island4x4
Engine Electrics - Island 4x4 - Specialists in Land Rover and Range Rover Parts and accessories for all models. UK and worldwide mail order.

But check your Vin Number as the last one on the list is the later models from XA41XXXXX