Faulty Temp Guage

[TeamSid]

The temperature guage on my '88 2.1(DJ) Caravelle appears to be telling me that the engine's running hot, about 3/4 to full stroke on the guage. The previous owner fitted an aftermarket guage (Just Kampers) and wired it into the existing wiring using the original temp sender. It always sat at 90 -100 degrees. I have put everything back to normal as I prefer to use the original guages as VW intended.The engine appears to be running at a reasonable temp as the cooling fan appears to be working correctly and has only come on a couple of times during extreme conditions. When starting the engine from cold the red LED flashes on as normal and the guage slowly rises as the engine heats up. I tried fitting a guage from an old Golf which gave me the same readings. I've also changed the small thermal transistor (TCA700Y) on the back of the clocks with no change, and had the capactor check and is within its tolerance. Does anyone know what the problem could be? Many thanks, Ross.

[tonytech]

Have you read the Wiki? There is a calibration check for the gauge.
https://club8090.co.uk/wiki/Co ... alfunction

Does your fuel guage read (approximately) OK?

T

[TeamSid]

Hi Tony'. Cheers, I'll give the checks on Wiki a shot when I get a minute. The fuel guage appears to be working OK. It's showing full when the tank's full and empty when it's empty. I know this because I let the damn thing run out recently!

[Mocki]

i would be replacing the sender with a known good one, and checking the wiring condition in the engine end ......
maybe run a temporary signal wire alongside the original one to rule out high resistance in the loom?