Had to revive this thread... It seems that there is a fault with the Alfa air intake system that can lead to this occuring.
Windows will mist up on damp/humid days, and the blower fails to demist them effectively.
The Blower fan resides in the dashboard above the passenger footwell. It pulls air from either the cabin or the external environment depending on the location of a flap above the fan unit. This flap is controlled by two inputs:
1. The 'recycle' button on the dash.
2. The '0' or 'off' position on the fan speed control.
It has been found (
) that the flap can seize in the closed or open position. If the actuator from the motor has broken, the flap will move to a free-moving swinging position.
By resolving this problem, you will also help prevent the build-up of exhaust gasses which do not exit from the system through the tail-pipe.
If the car constantly mists up perform the following:
1. Remove the front wipers.
2. Remove the black plastic aprons above the wiper motor assembly by removing the three hex screws retaining them, and pulling the aprons away from the windscreen. If you want to disconnect the washer pipes from the aprons, pour hot water on the pipes around the connector. This will expand the pipe enough to remove it.
3. Starting from the passenger side, partially remove the rubber seal on the top of the firewall to expose the plastic legs of the air intake cover. This cover prevents splashes of water from entering the air intake.
4. Note the location and orientation of the cover and it's legs, then remove it to expose the air intake.
5. With the ignition on, enable the blower fan unit and ensure that the 'recycle' option is not on. ('Recycle' is an arrow in a 180 degree turn).
6. Observe the yellow foam covered intake flap in the air hole. It should move out of the way to expose a path to the fan blades when the blower is active. If this does not occur, or if the flap is moving freely not under control of the motor, it must be secured in the open position.
7. To release a seized flap: With the ignition off, push down on the flap until it comes free. (This may damage the motor linkage, but as it's non-functional it isn't a concern).
8. Use a thick piece of wood doweling to solidly prop the flap open. Ensure that this wood cannot come free, as doing so will allow it to foul the fan blades. Use a silicone sealant or other glue to retain the wood.
Good tip... You can sort out wiper-judder at this point
9. Reassemble the intake cover, rubber seal, washer pipes, aprons and wiper blades.