Luke warm heat 92 Eco

[92EcoDiesel Jetta]

I got the cover separated from the center dash vent. Problem was the plastic was too cold and stiff. I heated it with a hair dryer and after some twisting it separated. The blend door foam was 90% gone. The foam is only on one side of the blend door (blower side). There is no sign of any foam on the vent door (the front one). Is the vent door foamed from the factory? The way mine look and feel, I'd say it was not covered.

[TylerDurden]

Yeah. Both sides were originally covered, on both doors.

The optimum is to cover both sides, but just one side should be sufficient to route most of the flow the desired direction. As I noted earlier, a 1/4" overhang of cover can help seal around the perimeter of the doors when fully open or closed.

[92EcoDiesel Jetta]

Got both the blend door and vent door covered today! I used aluminum duct tape in mutiple small pieces and snuck them on by hand. It should last much longer than the foam crap! What a difference! I can't keep my hand at the heat coming out the vent door, it is that hot!

Thanks for all the help!

[scrounger]

I have been planning on refurbishing the heater system on my vw too. That sounds like an excellent way of recovering them. I have used on heating ducts and has very tenacious glue. Thanks for sharing. 

Did you cover both sides so that the glue layers are touching?

[92EcoDiesel Jetta]

It is impossible do do both sides unless the heater box is removed from the car and disassembled to get the doors out.

[TylerDurden]

Not impossible to do, if you have the dexterity of a surgeon... or are a glutton for punishment. But not really needed, if good tape is used.

The PO of my '89 used crappy masking tape on one side only. 

[TylerDurden]

Getting the plenum back can be a chore, tho... that is, getting the ducts for the outer vents to connect to the plenum as it's going back into place. That's when having the radio out to get another hand in there to guide the pieces together can help. If needed, the control lever bits can be unfastened and pulled forward some.

[92EcoDiesel Jetta]

Getting the plenum back can be a chore, tho... that is, getting the ducts for the outer vents to connect to the plenum as it's going back into place. That's when having the radio out to get another hand in there to guide the pieces together can help. If needed, the control lever bits can be unfastened and pulled forward some.

I plan on leaving all the pieces taken off as is till it's warmer (spring). Rebuild the doors of my spare heater box over the winter and do a swap spring time. I have a crack free dash that I can install then also. Plus I may think about getting the AC working since I have all the parts from the 60K Eco parts parts.

While the dash was apart, I got the cluster out and undid the mod on the tach which was previously converted to a mag pickup and made it a W terminal. The mag pickup worked fine, it's the trigger magnets that keeps flying off that was a PITA. I am glad to get rid of all that junk by the crank pulley, which was in the way changing belts.

[TylerDurden]

10-4. When I took apart my ECO engine, I found loose magnets stuck to the block behind the timing belt cover.

[92EcoDiesel Jetta]

10-4. When I took apart my ECO engine, I found loose magnets stuck to the block behind the timing belt cover.

I know where my magnets are from, but where are yours from? I don't think there are that many mag pickup tachs out there that uses magnets.

My heat is working great again. From a dead cold start, I drive for 5 blocks and I have warm air coming out the ducts with the temp gauge still dead cold.

[TylerDurden]

I know where my magnets are from, but where are yours from? I don't think there are that many mag pickup tachs out there that uses magnets.

I don't know where from (they were on the engine when I got it), but they had little spiked feet to grip onto stuff.

[scrounger]

I went over to my neighborhood Ace and they had the metal tape with diagonal fiberglass fibers in it for strength and they also had one with a bit of insulation in it. Still too cold to take the dash and ductwork out but I think I am going to use the tape with the diagonal fibers in it.
92 eco diesel and others thanks.

[92EcoDiesel Jetta]

After taping up the blend doors and have excellent heat again, I took it for an hour long drive today. Not as cold (25F) as the last drive (12F) but I had great heat. Had to lower the heat lever to a little past middle. If I put it on max, it'd be too hot.\

At the rest stop I observed the following:
Uppper Rad hose 180 F per IR thermometer
Lower Rad hose cold per my fingers
Heater core hose in 180F per IR thermometer
Heater core hose out 170F per IR thermometer

Another thing I notice is my temperature gauge now sits a little past the middle. I have a 195F thermostat and that is normal position of the temp gauge in warm weather. The car seems to run better with ease of power delivery.

I'm a happy camper!

Last night in 12F ambient, driving on the hwy for an hour I was getting lukewarm heat. Last winter I had great heat.

92 Eco with AC.

I pulled over at a rest stop and noted the following:

1. Coolant temp gauge in the middle

2. Upper rad hose hot, 180F per IR thermometer

3. Lower rad hose cold

4. Upper part of radiator fins hot

5. Bottom of radiator fins cold

6. heater core hose in hot, 180F per IR thermometer

7. heater core hose out hot, 160F per IR thermometer

I think all of the above is normal for 12 F ambient and the thermostat and heater core is OK.

Why am I getting lukewarm heat?

Per the Bently, the amount of heat is controlled by blend door. I assume it blends the ratio of cold fresh air vs hot air from the heater core? Am I getting too much cold air because the blend door is out of adjustment or can it be a vacuum problem to the servos?

I don't want to rip the dash apart to find where the problem is. Is the blend door cable on the heater box accesible without ripping the dash apart? Maybe it's just a matter of adjusting it?

[92EcoDiesel Jetta]

Yeah. Both sides were originally covered, on both doors.

The optimum is to cover both sides, but just one side should be sufficient to route most of the flow the desired direction. As I noted earlier, a 1/4" overhang of cover can help seal around the perimeter of the doors when fully open or closed.

It just occurred to me that the overlapping foam on the doors helps seal the perimeter of the doors (while under air pressure). It does not explain the holes in the doors, however.

[92EcoDiesel Jetta]

I did the blend doors in my 89 and the heat still sucks. The core must be plugged.  Pulling the airbox is a PITA. I have heard guys have split the evap section off and removed just the heater section, but that can't be any fun either.

Did you get this fixed? A quick way to tell if your core is plugged is to feel the supply and return hose. If the return is cool to the touch, the core is plugged