Hi all,

Hoping someone can offer some advice. My Felicia (Percy) has always run quite warm according to the guage so have changed the thermostat & temp sender but nothing seemed to change. Figured I'd keep an eye on the guage & live with it.

Then the guage started not reading untill it was about quarter temp then worked ok.

The car has been relaxing for about a month untill today when I took him out, covered about 18 miles & no movement at all on the guage - any ideas what could have upset him?

If I'm interpreting "the gauge started not reading until it was about quarter temp then worked OK" as the gauge suddenly jumping off the bottom to 1/4 of the way up then that suggests it's an electrical issue, either with the gauge or the sender - see the "common issues" sticky for TeflonTom's info on how to check the sender. If you have access to VAG-com/VCDS you could also check the temperature readout from the ECU. If the sender checks out then you'll need a new gauge (which may entail a whole new instrument panel). It may also be worth double-checking you have the correct sender for your engine - my 1.6 has a yellow-banded one, but the thermostat repair kit I got from Jorily contained a blue one, which made the gauge read artificially high (luckily the original was fine - I just tried it to see if there would be a difference).

Have you noticed the fan cutting in at all? If it does, you know the engine is warming up OK. If not, the easiest way to check the thermostat would be to warm the engine up while feeling the difference between the top and bottom radiator hoses near the engine - if the bottom one gets substantially hotter than the top one to begin with, then after a while the top one gets hot too, that suggests the thermostat is working as it should. If the two remain relatively equal in temperature, that suggests the thermostat is stuck open (usually caused by the plastic housing disintegrating).

I'm also assuming we're talking about a petrol engine here - most of the above probably applies well enough to the diesel but I can't guarantee the specifics as I've never owned one.

Add to Robin's post - old trick to check on sender /gauge used to be to switch on ign, but not engine,. Then remove sensor wire from sender . Gauge should go to lowest point. Then earth wire -gauge should go to highest point . That proves gauge is ok - time for a new sender .

HI

Which wire do you earth? Gauge has not worked for ages but now I have to change radiator. Would like to get it working before I do that.

Regards

T