I've just done a search for this subject but couldn't find anything so here is a question - can anyone please help?

I have a MY99 sport but the general layout of the interior is the same as the turbo.
My problem is the radiator temp gauge on the dash. It has been doing a full scale deflection (completely off scale to cold) everytime the engine is cooled down. If should settle down at approx the 9 o'clock position but it just goes down towards the 7 o'clock. When the engine is warm it reads normal.. have you ever experienced this? or have any idea whatsoever it could be?

I had this problem a few months ago, and it seemingly got fixed but it has started doing it again. I'm just wondering if it is a lead that has come lose somewhere or if it is a big problem.
Thankyou for any help in advance,
Ian

 

Had similar sorts of problems on other cars. This symptom tends to suggest air/gas in the cooling system and its getting trapped around the temp sender giving false readings. When the car cools gas will rise to this point. When it is warm and engine running the water pump will break the air into small bubbles and distribute them round the engine.

Have you had coolant changed recently (done as part of one of the services, but can't remember which)? Could be that it wasn't bleed properly afterwards? Try getting system bleed again and see if that stops the problem. If it comes back after a period of time. If it does gas is getting into coolant somewhere.

It might be worth replacing the sender itself, as these are relatively cheap and it will narrow the causes down a bit.

I have to say that on my 306 that funny temp guage reading was gas in the coolant. It was the first sign of the head gasket going. I hope it isn't in your case, but should be covered by warranty. Get your dealer to check it out.

 

It could be something very simple like the ground on the gauge not being good. I'm afraid I don't know where the sensor is, but if you find it then check the electrical connections.

I had this on a Renault 19 16v, and cleaning the terminals fixed it IIRC.

Anyone know where the sender is?

 

The last-time i got one of our mechanics at work to have a quick look at it and he fixed it in minutes. He however doesn't work here anymore and i think it is something easy. ( I'm sure he said it was a connection coming loose but i have no idea where or what to do if i find it)

I'm abit conecerned about the head gasket story now! But the car is about to go in for its 37,500 mile service next month so i'll get it all sorted out then.

Too many things have started acting wierd with the car in the last few weeks, with a faulty door window , a funny noise when the engine goes above 4000rpm in 4th gear and now this again. Was just hoping that the engine noise and this were not connected but i don't think it will be. I'll get it to the dealer asap.

Thankyou very much for replying.