Hi. Temp gauge on my 03 1.9 octavia was acting wierd for some time, slowly getting up to 70 deg celsius and then dropping. The last 3 weeks it's just dead, lies on 50 deg all the time. Replaced the ETC but still the same. Ran diagnostic but no errorcode. The radiator hoses gets warm, the heater gets warm, the car does not overheat. The only other issue is that the car revs when starting it. Has been like this for a year or so. Anyone with pointers would be much apreciated.

Hello and welcome

 

 

Is that a typo "ETC" or another name for the CTS - Coolant Temperature Sensor?

 

CTS failure is common, and does what you describe. 

If you fit a non genuine replacement sensor, you have about a 40% chance of it working, and 20% of getting more 12months of it working...

 

 

*stats are somewhat made up, but anecdotally speaking -  get a genuine part, vag engines dont like  on genuine sensors

It was a typo.. It is the coolant temperature sensor (Engine Coolant Temperature-sensor) 

I don't think the sensor is genuine. I'll contact VAG and get a genuine one. Thanks for the tip.