Coolant temperature

1.8T 99 passat. During highway driving, although not always, the temperature is wandering around between 190F and lowest mark. Whenever I slowdown or stop, it comes and stays at 190F. It happens more when driving at 80-90mi/h. Anyone knows what can be checked?

1.8T 99 passat. During highway driving, although not always, the temperature is wandering around between 190F and lowest mark. Whenever I slowdown or stop, it comes and stays at 190F. It happens more when driving at 80-90mi/h. Anyone knows what can be checked?

Have you checked or replaced the thermostat?

I think that the problem is in the sensor because over the weekend the temperature read minimum, but hot air was coming out of the vents. I'll check connection and/or replace/clean the sensor.

just replace the sensor its about 10.00 at the dealer

Mine did this as well. You need to make sure that you dont have any leaks in the hose's and also make sure your ball is to the full line, other wise this cause's the temp to go all over the place with the 99 Passat. If your still having problems after chaning out things, try asking the VW dealer, sometimes they are able to talk you through things over the phone. :)