Heater Trouble?

[Dub_Dude_16v]

Hello dudes!

Wondering if a could get some help off your guys please.
Alongside my mk 2 16v i also own a G reg mk 2 1.3 (2G engine code). When the engine is hot and the heater is blasting away on full there is hot air. When i stop and idle the air goes cold?  Anyone come across this before? I thought maybe it was a dodgey thermostat. Also even when the weather is freezing outside the temp gauge is up just over the half way line. On another mk2 1.3 i own as well the temp gauge never really moves outta the white part even when hot?? lol hope that makes sense 

Thanks!
Stevo. 

[jezza16v]

Heater by-pass valve - refer to mk2 maintenance & info section, its the first topic, did this myself at the weekend. Try using the 'search' facility, there's loads of stuff on this...

[Dub_Dude_16v]

Thanks for the tip matey! Although one of the cars hasn't got the heater bypass valves fitted. Neither has my 16v  Obviously never got called up by VW's recall campaign.

[rubjonny]

ok 3 possiblities left:
low coolant
water pump is about to die
matrix is clogged

Might possibly be the stat, but I doubt it.  Run the car from cold and check the bottom hose, it should stay stone cold till the temp gets to half way, then start warming up.