I took my car down the M1 for the first time today. When the car is up to temperature which is half way on my gauge, every so often the needle went down a bit for a few minutes then came back up to normal. Any one else had the same problem ?? Is the thermostat knackered ??

 

Hi,

I'm assuming you have owned your car for a short period of time.
If this is the case, you will find the engine is known to have a problem with running hot and the temp gage with show an increase in temperature. I had my coolant system and block power flushed, new coolant and new thermostat installed and still it the temp gage will show an increase in temperature. Par for the course owning a TT.

 

You've got a green-top temp sensor, right? Known defect with the black ones, they'll read all over the place.

 

Yep, I've had a green sensor fitted and a new water pump but still the same. I'll do the thermostat next