Dash Vents Blowing Hot Air

[magpie21]

All four of my dash vents continually blow hot air no matter what the temperature setting. The car has aircon and the vents by the steering wheel blow ice cold air but the dash vents blow hot air at the same time.

Any suggestions as to where I can start to diagnose the problem?

Cheers

[B3NNL]

It sounds like the stepper motor for the flap in your heating system. I had the opposite, no hot air!
It's not that hard a job to get to, but will involve some dissassembly!
Take your main bonnet off and the scuttle plate (two screws either end and your wiper assembly's.
looking at the car from the front, top right hand side you'll have two boxes, one black and one covered in tin foil insulation.
you need to get into the black one. Remove all the securing screws. Jently but firmly wiggle the box out of the bulkhead, there is about an inch that goes into it from the box.
Now look into the letterbox shaped hole and you will see a small motor with an arm connected to a flap.
The failure is usually that either the motor fails or the flap gets corroded/stuck in one position.
I got someone to sit in the car and adjust the temp so I could see what was/wasnt working. I then helped the flap to move a tad and it all started to free up, a bit of WD40 was sprayed in just to aid things and its been fine since.

[magpie21]

Thanks for the advice. I'll give it a try this weekend.

Cheers

[S6PNJ]

There are two air feeds into the dashboard area, one is hot and one is cold (including air con feed). See this topic for a better explanation and pictures etc
http://www.pistonheads.co.uk/gassing/topic.asp?h=0...
From recollection nearside feed is hot, off side feed is cold and air con. It is unlikely to be the flapper if you are getting hot from one and cold from the other as they all feed from the same area. I'm assuming you have a Mk1 (ie original) Tuscan, I'm not sure how the Mk2s are configured.

The air feeds into the dashboard and then either out of the 4 air vents to the windscreen, or back down the rectangular hole into the various pipes that split it to the rear screen, foot wells and steering wheel housing.

All AFAIK or can remember!

[dvs_dave]

S6PNJ said:

The air feeds into the dashboard and then either out of the 4 air vents to the windscreen, or back down the rectangular hole into the various pipes that split it to the rear screen, foot wells and steering wheel housing.

Almost right! The feed for the steering wheel vents T's off from under the main cold air feed pipe before it enters the dash plenum. That's why it only blows cold air, or no air at all when on full heating.

[nawarne]

Does sound like the heater stepper motor not operating the flap.

When you've removed the black plastic plenum as described by B3NN above, and you've 'worked' the heater temperature knob...and hopefully got everything moving, I'd confirm that the flap makes a reasonably good seal on both the 'hot' and 'cold' input ducts. The flap effectively diverts the air ex the fan to either the hot matrix or the cold/aircon matrix. A good seal makes sure that you get maximum heating or cooling when the cabin knob is set to full hot/cold.

Nick