I have a frustrating problem with my R19 1.4e. Recently, the car has started to "overheat" according to the temp gauge. However, I believe the problem could be with the gauge itself.
Before, the gauge needle would hover around halfway when warmed up. It would never come close to going in the red zone. When stuck in traffic, the temp would rise a bit above half way at which point the fan would cut in and reduce the temp. All perfectly normal.
Now, once the needle reaches half way it suddenly shoots up into the red zone and stays there. Even if the engine is switched off and the car left standing, the needle doesn't go down for ages (say 1/2 hour) at which point it plummets to the bottom of the gauge. Strange.
The fan doesn't come on any more often than it used to. When it does come on, it'll stay on for maybe 20 seconds and then switch off. The action of the fan doesn't reduce the gauge reading at all.
From this, I suspect a fault with the gauge or its sender. My reasoning is - if the car was constantly running in the red zone wouldn't the fan stay on all the time and only switch off once the temperature had been reduced? The fan and gauge are controlled by separate devices - the fan by a thermostatic switch in the radiator, the gauge by a sender in the cylinder head.
Apart from the gauge reading, the car has no symptoms of overheating.
-Thermostat has just been replaced (in an attempt to fix the problem)
-Car does not use any coolant
-No signs of head gasket failure
-The rad does not appear to be blocked internally or externally. The rad warms up as it should once the thermostat opens.
-Hoses seem OK
-The cooling system and rad have recently been drained, flushed, refilled and purged of air. Again this was an attempt to cure the "overheating".
-Water pump was replaced a year ago. There is a good flow of coolant through the expansion tank so the pump seems to be pumping normally.
-Heater works fine
-Generally, the car runs perfectly
But I'm still worried about overheating and I don't like driving without the use of a reliable temp gauge. I've had enough experience with renaults to know that they can be prone to cooling system problems/overheating. So I rely heavily on the gauge.
So what do you guys think? TIA for any tips!
brian