mk 4 thermostat

[Jay]

Hi all,
just a quick question.
My 1999 mk4 golf needs a new thermostat. It overcools when given high revs. It only overcools by about 2 clicks.

Will it be o.k if i leave it for a few weeks, or could it suddenly overheat

Thanks

[NicholasP]

Sorry I cant help..would just like to add that my golf does this too..when pushed a bit, engine temp drops from 90 deg to about 78...

Why's this happening?

Nick

[Jay]

I've had hours of fun trying to work this one out.

At first i thought it was temp sender. Changed this twice, didn't work.

Cleaned all wiring and connections still did nothing.

The whole way through all this it had been code read about 5 times, no faults showed up.

By this time i was going a bit daft.

Anyway after a lot of stress asking questions and scratching my head i've decided it must be thermostat, there is nothing else that could be doing this. (unless somone else has any ideas)

Does your gauge go down and straight back up, or does it stay there for aq few minutes and come back up slowly.,