- A couple of weeks ago the car started to overheat, the coolant popped out from the cooling system surge tank through the cap.
- The radiator was cool, the pipe leading from the termostat was barely warm. The decision was changing the termostat. The fluid was changed and a new thermostat sensor as well (Termo. Behr and the sensor EPS). Off I went and... NO CHANGE. Again the car started to overheat.
- I went a mechanic and the dignose was changing the radiator (according to his experience and knowledge).
He changed it and added a better coolant.
NO CHANGE, even worse.
- Now accelerating above 100km/h (or just exceeding 3500rpm) ends up with stopping the hot/warm air to blow inside the car and the temperature rising to 120 degrees. I opend the hood and the radiator was cool, the thermostat extremely hot. The pipe leading from the thermostat to the radiator was barely warm (and the pipe under it was just cold) [as previously]. The coolant was boiling.
- The fans were working at their highest speed. After a couple of minutes the fans dropped in their speed and at the end they stopped, the coolant stopped boiling and was luckily let into the radiator. The temperature dropped immediately and the hot air inside the car started to blow again.
- How on earth can this happen?
- Is it possible that a new and original thermostat was also damaged and a new sensor as well?
- The mechanic stated that the problem was with some kind of powder which was put into to cope with some leaks.
- Anyway, I've got a new radiator, thermostat, t. sensor, and NO CHANGE at all
However, we did one trick, let's say, namely we took the old thermostat, took out the guts and I had an open circulation. The car couldn't warm up at all while driving, even with speeds 160-180km/h (sic!), however it did warm up when it stood still, strange though it was.
- When we put a brand new original thermostat and a new sensor the situation started to worry us again.
- The mechanic still considers the remaining 'stuff' (sealing powder for radiators) to be the cause of overheating, moreover, the duct heater can be jammed with the 'stuff' into the bargain.
- But how is that possible, that I drove a 100-kilometer trip to the mountains with the nominal temperature and the hot air blowing inside, and suddenly, when I overtook several cars (140kmh), and back to 90kmh, the car starts to overheat and there's not warm or hot air inside and the radiator is cool and the thermostat is hot, the coolant is boiling? After some time it yields and works normally, the temperature drops and the radiator is filled with the coolant? Help