I have a 99 jetta wagon 1,9 TDI. I had problem with a coolant-leak. Since it was time for a timing-belt change, I changed waterpump, thermostat, temp-sensor, heater-core and checking blend-doors. So all that is new and fixed. I've flushed radiator, heater-core several times. First i suspected the thermostat not to open properly, so I bought a new OEM one. Have good flow and no leaks, but there isnt comming any heat in my heater. After the engine is properly warm (90celsius) if I increase RPM I get a little warmth(Very little) but is disappear Very quickly when I turn up the fan.
any good tips?