Airco on a '99 Impreza Wagon switches on and off every few miles ( noticable from engine load and slight noise increase/decrease ), while NOT maintaining pleasant temperature inside) is this normal operation? While running idle the AC system produces a very loud humming noise. Something vibrating near the fan housing. This can't be good, but happens only with higher outside temps (+75 F..)
The dealer tries to put me off, but I lack AC knowledge to improve his diagnostic.
Anyone any thoughts?
Thanks, Gerard.