Engine coolant temperature low

[DougL]

My car is with the dealer now. They have told me that they have had to dismantle the front end to replace the thermostat. There is apparently at TSB (technical service bulletin) about this problem so it is evidently more common than we think. The car went in on Thursday. It is being rebuilt today (Friday) but we won't have it back til Monday.

[Hawaii-Five-O]

Right then.

Just got the car back from the dealers. It was indeed a faulty engine coolant temperature sensor. All replaced under warranty.

I asked the service advisor if there had been a VW bulletin issued about this fault - they said no.

Anyway, on the drive home from the dealers the ECT gauge performed exactly as I used to. Getting up to 90°C quickly and staying there. I'll monitor my fuel economy over the next few days to see if it improves. As others suggested I think it was running rich (hence the dip of about 10%).

Nice it's fixed but slightly peeved it broke in the first place on a car that was only 11 months old.

They even gave me a 1.5 litre bottle of genuine VAG coolant to top up with if needed. Think it might last me a whole lifetime