Hi,

I have a 2002 A4 1.8t, until now it has run pretty sweet, the coolant temp gauge is sticking at the cold position even when I know the engine is hot, when the vehicle is in motion the temp stays low, when i idle the engine when parked it goes to 90c and will stay their no probs until i drive off when it will cool down quickly.
I have also noticed now, instead of the airpump being noisy on cold start the coolant fan comes on about 30 seconds after start up, then goes off after a short while. ( only when the engine has been shut down for over 1 hour).

I fitted a Carbonio Induction kit and a cat-back Milltek twin exhaust system around 4 months ago, it has ran fine until the really wet and cold weather hit the UK.

Any one have an idea on a DIY fix?

Thankyou in advance.

 

either the thermostat is out or you need a ECT sensor, id try the sensor first since its a rather inecpensive item. if the problem persistes i guess oyu looking at a new thermostat.