Better Heat?

[Riverman]

Any common reasons that I would have little heat out, even with engine at operating temp. Plenty of air flow.

[rabbitman]

I assume this is a mk2 from your other post. It's probably the blend door, this shows how to fix it. I've never done it so I haven't a clue how long it takes.

http://forums.vwvortex.com/zerothread?id=2355434

[TOW'D]

replace the thermostat with a new one
hank

[jtanguay]

I assume this is a mk2 from your other post. It's probably the blend door, this shows how to fix it. I've never done it so I haven't a clue how long it takes.

http://forums.vwvortex.com/zerothread?id=2355434

this is a really good writeup with lots of pics.. I had to do the same rebuild for my blend doors, etc. the foam crumbles to dust its so old!!! neoprene would be ideal but a little bit $$$.

I have to say that after i flushed my cooling system with prestone heavy duty flush, the heat has never been better. I assume that this is from removing deposits in the coolant passages that reduce the heat transfer. there are also some additives out there that increase the heat transfer such as redline water wetter, and I've tried a product called tow-kool with great results.

thermostat is also a great idea to check. always test it in boiling water with a thermometer to ensure it opens and closes at the right temp. worst case scenario however, would be a failing water pump...

[clbanman]

I just did the blend doors on mine (91 Golf).   Had so little heat the windshield wouldn't even defrost.   I did a bit of a shortcut on the vortex writeup as I was too lazy to take the entire heater box out and disassemble as he shows.   I removed the centre console, knee bars on both sides, glovebox assy, centre vents and ducting.   At that point I could see the blend doors.  I bought self-adhesive foam sheets from Michaels ($1.29 each - used 2).   My first attempt ended up with the sheet not adhering to the door (hadn't cleaned the doors and only used the sheet on one side).   Sprayed some brake cleaner on a towel and wiped down the doors as much as I could.   Access to the front door (air direction control) is pretty good.   Wrapped the sheet around both sides so the material would adhere to itself through the holes.   Worked fine.  The cold air door is trickier in the car as access is difficult, at least with hands as big as mine.   I got the wider section by using two pieces (top and bottom half)  and wrapping them around by manipulating the door position and getting my fingers as far around the back side as I could.    The shorter leg on the door was trickier.   First shot I managed to get my fingers in behind the door and as I curled them around to press the sheet to the back of the door, I sliced my fingertips on the fins of the heater core.   Grabbed a plastic coat hanger and cut a candy cane shaped section, heated over the stove to get a reverse bend and used it to push against the rear of the door and seal the foam sheet to the door.   So far so good, and I actually have had to turn the heat down several times as the car was getting too warm (not this morning though).

[theman53]

This absolutely pisses me off. But at least I didn't go any further...
    I have to say thanks, becuase without  this write up I would have never known. I just did the A/C evap and heater core in the Jetta in my build thread. The foam was gone, none, not even any evidence it was ever there, so I didn't even think anything was wrong with the metal door with holes in it. Now I have to take it out and do it again. The reasons I am so upset are 1. It is too cold for me to work on the car and that is also why the engine isn't in yet. 2. I hate dealing with heater cores- why I replaced it now eventhough it didn't need it yet. 3. I had it almost completely back together. 4. I hate dealing with heater cores. 5. It seems with this car it has always been 3 steps forward 2 steps back.  End rant.

Anyway thanks for the link and letting me figure this out before I put the interior in and screwed the sides on.