HELP! Vents only blow hot air.

[nieuwhzn]

I'm not completely sure, but probably the Boxster has the same 'blend door' setup for its air handling as most other cars. The blend door is exactly what it says it is, it blends cold and hot air from outside and somewhere close to the engine, respectively. The door gets moved by a stepper motor which opens/closes the door depending on the temperature setting.
A malfunction in this system can be because the control of the stepper motor doesn't work anymore, the stepper motor is broken, the arm moving the door is broken or the blend door is stuck. All this stuff is underneath the dashboard somewhere. Turn the contact key on, don't start the engine and listen if you hear something moving when you ride the temperature setting up or down. If you don't hear anything then the system is probably malfunctioning.
Now, depending on where this blend door stuff is located this can be fixed for a couple of hundred bucks or over a $1,000. The problem is that in many cars the blend door stuff is located under the dashboard. This means that dashboard has to come out which is as expensive as dropping an engine. I don't know if this is the case for a Boxster.

[heliguy]

Originally Posted by nieuwhzn

I'm not completely sure, but probably the Boxster has the same 'blend door' setup for its air handling as most other cars. The blend door is exactly what it says it is, it blends cold and hot air from outside and somewhere close to the engine, respectively. The door gets moved by a stepper motor which opens/closes the door depending on the temperature setting.
A malfunction in this system can be because the control of the stepper motor doesn't work anymore, the stepper motor is broken, the arm moving the door is broken or the blend door is stuck. All this stuff is underneath the dashboard somewhere. Turn the contact key on, don't start the engine and listen if you hear something moving when you ride the temperature setting up or down. If you don't hear anything then the system is probably malfunctioning.
Now, depending on where this blend door stuff is located this can be fixed for a couple of hundred bucks or over a $1,000. The problem is that in many cars the blend door stuff is located under the dashboard. This means that dashboard has to come out which is as expensive as dropping an engine. I don't know if this is the case for a Boxster.

I'll listen for it today. Would it blow hot even with the A/C on?

[Porsche Chick]

You've blown a fuse.

Easy to fix.

I had this happen once, but it was an old school Toyota, and they came with spare fuses in those days . . .