Hey, I have a 91 Coupe Quattro. Every once in a while I get a water temp alarm. The water temp gauge is allways on the low end when this happens and if I pull the cap off the overflow tank the water is warm but I can put my finger in it just fine. This first happened several months ago but has been very infrequent, once every couple of months, until recently. It's happening every other day or so now. If I turn off the car and start it right back up the alarm goes away and sometimes it comes back in a couple of minutes and other times it doesn't. It's super annoying and I was wondering if anyone else has had this problem or has any ideas. Thanks.

 

I have had these problems in the past with my 4K and 100Q. Check the thermostat it might be stuck closed. Next check the temperature sender and the thermo switch, two separate items. The electrical contacts have a tendency to corrode so check them as well.