Good morning Sirs.
I have been experiencing trouble/discrepancies with my 2000 FORD LYNX 1.6L. The discrepancies are as follows:

a.) Whenever I turn the aircon, the rpm drops down instead of going up. I already had my servo cleaned and it's still the same, what do you think is the problem? Do i have to replace the servo? it's a bit expensive. :-(

b.) whenever I come from a stationary position, for example when I park, and engage my handbrake, then when i leave or go into motion I hear a grinding sound. But as i have observed, this only happens when i turn off the engine. When I'm stuck in traffic and in stationary, I never hear the grinding sound. What do you think causes the grinding sound.

c.)Also, I had just changed my pressure plate, clutch disk, release bearing, pivot bearing and had the fly wheel refaced. Problem is there this switch in the transmission that had broken wires, at first I thought it was a backing-up switch for the backing lights. But when I tried to check if it really is for the backing lights,by removing it, my backing lights were ok and working. What do you think is this switch located in the transmission for?

Thank you and more power.