DIY: How to fix air blend door MK4 TDI no cabin heat problem
Problem:
I was not experiencing cabin heat at any point during my commute. This was becoming a serious concern not only because I was freezing, but also because I couldn’t defrost.
The coolant temp sensor said a solid 190. I knew my temp sensor was good as I replaced it recently, and the thermostat was also fairly new. I had installed 2 plastic sheets in front of my radiator to reduce air flow. The bottom cover of the engine was intact, and I re-insulated my top engine cover as the foam was not present.
I was not seeing any foam coming out of the vents, but since heater cores aren’t typically faulty, and my directional heating/cooling was not functioning, I decided to attempt a blend door repair without removing the dash.
I followed this on VWVortex, but hopefully I can clarify a few things in the procedure that may help others: http://forums.vwvortex.com/showthread.php?5984439-Mk4-blend-door-foam-repair-diy
Parts:
Aluminum insulation tape
Cleaning solvent
Miscellaneous torx, phillips, and flat-head drivers
Dremel
Procedure:
1. Remove plastic paneling under the driver’s side.
2. Remove the center console.
3. I got away with not fully removing the glove box, but it would probably be easier to just get it out of the way when you take the center console out.
4. Remove the center trim around the radio and HVAC controls.
5. Remove the controls and push them into the driver’s side foot bay.
6. Remove the radio and connections.
7. There are multiple hex head 8mm screws that hold down the vent casing behind the radio and controls. I could not get any sort of tool in there with a plastic corner that holds a radio wire bundle clip. I used a Dremel to cut the plastic out so I could get a straight angle on the screw.
8. I didn’t fully remove the vent case, so I just pushed it down far enough so I could reach inside the heat exchange.
9. To access the doors, you must move your HVAC direction controls. I used a solvent to clean off the doors. Cutting length size pieces of tape, I was able to get one hand in there to attach them to the 3 doors. I used approximately 4 strips per side, per door. I was careful to make sure the tape didn’t rub on the door pathway when I moved the HVAC controls.
10. I cleaned the center piping going out to the cabin, and noticed that the piping was not attaching well to the airway. I taped the two plastic pieces together as I was re-assembling.
11. Install HVAC controls, radio, and trim. Install the center console and glove box. Install the rest of plastic.
The car begins heating immediately. I can tell the air recycling button does a lot more, and I can successfully direct air to my feet or my dash.
Cheers
Problem:
I was not experiencing cabin heat at any point during my commute. This was becoming a serious concern not only because I was freezing, but also because I couldn’t defrost.
The coolant temp sensor said a solid 190. I knew my temp sensor was good as I replaced it recently, and the thermostat was also fairly new. I had installed 2 plastic sheets in front of my radiator to reduce air flow. The bottom cover of the engine was intact, and I re-insulated my top engine cover as the foam was not present.
I was not seeing any foam coming out of the vents, but since heater cores aren’t typically faulty, and my directional heating/cooling was not functioning, I decided to attempt a blend door repair without removing the dash.
I followed this on VWVortex, but hopefully I can clarify a few things in the procedure that may help others: http://forums.vwvortex.com/showthread.php?5984439-Mk4-blend-door-foam-repair-diy
Parts:
Aluminum insulation tape
Cleaning solvent
Miscellaneous torx, phillips, and flat-head drivers
Dremel
Procedure:
1. Remove plastic paneling under the driver’s side.
2. Remove the center console.
3. I got away with not fully removing the glove box, but it would probably be easier to just get it out of the way when you take the center console out.
4. Remove the center trim around the radio and HVAC controls.
5. Remove the controls and push them into the driver’s side foot bay.
6. Remove the radio and connections.
7. There are multiple hex head 8mm screws that hold down the vent casing behind the radio and controls. I could not get any sort of tool in there with a plastic corner that holds a radio wire bundle clip. I used a Dremel to cut the plastic out so I could get a straight angle on the screw.
8. I didn’t fully remove the vent case, so I just pushed it down far enough so I could reach inside the heat exchange.
9. To access the doors, you must move your HVAC direction controls. I used a solvent to clean off the doors. Cutting length size pieces of tape, I was able to get one hand in there to attach them to the 3 doors. I used approximately 4 strips per side, per door. I was careful to make sure the tape didn’t rub on the door pathway when I moved the HVAC controls.
10. I cleaned the center piping going out to the cabin, and noticed that the piping was not attaching well to the airway. I taped the two plastic pieces together as I was re-assembling.
11. Install HVAC controls, radio, and trim. Install the center console and glove box. Install the rest of plastic.
The car begins heating immediately. I can tell the air recycling button does a lot more, and I can successfully direct air to my feet or my dash.
Cheers
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