I have a 1996 GMC Jimmy and the A/C works great except when i go to accelerate it will stop blowing out the vents that is pointing towards the driver and passenger and either go to the floor or to the defrost usually the defrost vents and then once i stop accelerating it will return to the normal vents. This happens anytime the truck is put under load even if its just going up a hill. Any ideas y?
Thanks matt