A/C compressor is permanently driven with variable output (no clutch).
I would focus investigation under the pollen filter.
Open the bonnet
Remove rubber seal (weather strip)
Remove left and right plastic cowels (where the brake fluid reservoir peeps through.
Use a large flatblade screwdriver to press and undo 4 plastic retaining screws 90degrees.
Lift pollen filter housing and filter together towards you and upwards while holding filter in housing underneath with your fingers.
Look into void covered by filter.
Operate recirculate and observe flap actions and noises.
When reassembling, ensure that the 2 spikes on the windscreen cowel insert into the rubber gutter spouts on filter housing.
Another thing is air is entering the car and has to leave somewhere, normal place is vents behind the trim in the boot but could be a gap in windows or doors, check windows are shut and sealed. In recirc mode, the air is no longer leaving the car so no whistle in any holes or gaps.
|