My 2000 jetta turns off after 10 min when temp hits 190. just like turning the key. the engine is not hot I can put my hands on it. I've replaced all fuses and fuel pump is working. if I let it sit 1\2 hour to an hour starts right up but then does the same thing 10 min later.

Heater core is not working.

Had this happen to my '99 Dodge several years ago. Wasted a lot of money trying to figure it out. I believe it ended up the fan relay switch- cost about $50. Took less than 10 minutes to switch it out.

shifting solenoid - either they work or do not,. otherwise look closely at the wires going into and inside the transmission

Best regards
Ck

Hi.. I had a very similar problem recoverrd to are workshop by the A.A around a month ago.
Exactly the same problem (left to cool started.? Once worm or hot engine just turning over ?)
Afdter reading all known folts and finding nothing to do with what I'd wanted. It took some time ?
Cutting it sort if found when I replaced a intermittent faulty fuel relay and run till engine hot (untill cooling fan cut in) Then turned off engine .. on turning key to see if this had cured my problem?
The engine started frist turn of key after repeating this a number of times .. this car was now starting fine (whether hot or cold)
Problem fixed..
Hopefully this will be of some help to yourselves
Hears hopping
Don Milward Premier Garages

Then replace the thermostat, because if on lower hose not hot and on upper hose scalding hot = antifreeze flow blocked by the thermostat wich remains closed!!!

Thermostat replacing:

try checking the throttle position sensor or the idle control valve both can keep it from running.

try replacing the sending unit, It is easy but did it when the car is cold

TDIs can take a while to heat up in cold weather. Sometime 10 minutes or more.

If it is taking longer than 10 mins for your temp gauge to hit 190, you may need a new temp sensor, which is pretty cheap and just pops into the engine block, almost right next to the battery.

defo the water pump.a very common problem you have got

with you using antifreeze you have 1 of 2 problems either a bad waterpump or a blown headgasket, i just put a head gasket on mine