Dash heater vent diverter not working??
 

I need some help. I have heat coming to the front when I pull the heater levers but 90% of the heat is coming out of the side vents that are located on the dash of my '89 cab....

I change the controls to defrost (windshield) and that works.
I change the controls to footwells, and thant does not work.

Help. What to do?:confused:

I have the opposite--nearly all of my heat goes to the windshield and very little to the side vents. I've been able to slightly improve the situation by checking out the cable connections on the fresh air system in the front boot. I lubed and manipulated the levers--that worked some. I intend to disassemble and reassemble sometime later this fall.

Anyone done this?

David

I did this as well and will try again. is this a manual connection or does the dash lever work a servo??

The levers on the dash are connected to valves on distribution boxes in the trunk, via cables that resemble bicycle brake cables. If you have somone operate the levers while you observe the resulting action in the trunk, you can figure out what needs to be fixed.

JR

I just did the "two man" check of the cables. Everything is working. I will test drive it and see. Could be that the actual flap is stuck. If so, were are the Flaps located in? I assume just inside where the wire is connected in the ducts in the trunk...

That's right--they're simple flappers without servos. The dash levers pull on the cable, the cable pulls the levers in the boot, those levers manipulate the valves. Its all mechanical, no special electrical components.

So like where is a good description of this silly system. One with diagrams, where stuff is located. The PORSCHE workshop manuals are useless, or at least the volumes I have (Vol III thru Vol VI).

How about a hint where to find the information.

There's a ton of info on this forum, if you can find it with a search. I know I have posted about in in many threads. Most of what I know I learned by woring on it. Once you have a few parts in your hands, it's easy to figure it out.

What, exactly, do you have questions about?

JR

Before you start pulling apart the flapper control boxes in the trunk, remove the footwell side panels and make sure all the hoses are connected and not cracked, then check the ones in the trunk too. If the hoses are good its a good bet the problem is at the cables at the flapper control boxes in the trunk as other's have mentioned. The cables are attached with spring clips that could slip or there was work done on them and they were not adjusted properly when reinstalled. The ends of the cables have screw clamps that could have slipped also. The Bentley manual has good pictures and a description describing the adjustment proceedure.

If the diverters are not property diverting air, then there are two thinks to check. First off one of the air hoses from the fresh air plenum and check the rubber on the diverter flappers. If rotted, take the fresh air blower housing off the plenum and take apart then make replacement rubber seals for the flappers using 1/16 " sheet rubber found in plumbing supply, works great, takes time to remove and install.

Thanks everyone, I plan on going in this weekend and checking it out...

its not that bad to take apart the cables and flapper boxes for a cleaning and lube. Take a bunch of digital pics because putting it back together can get a bit goofy.

Carefull with the little clips. You need needle nose pliers to take them off but wear safety glasses because they will fly.

My controls werent working because the cable housings had kinks. I used bike cable housing as a replacement. you still need to save the original inner wires. treat them with care.

And another comment about "before your pull too much stuff apart". Remove 2 screws that hold on the the floor vent covers, take a look and make sure the PO didn't cover over the vents to eliminate floor heat as my PO did. They all lived in Florida/Georgia and I have no idea why. When I removed a bunch of duct tape and plastic bag material, I now have plenty of heat to the floor where it belongs.