Losing power when defrost is on????

Here is my problem. When i use the front defrost my car it's almost like it's missing but not jumping. The rpm will be fine then it drop's a little then back and fourth and it's annoying and harder to go up steep inclines. Also it does it when i use the a/c but i figure that is normal. Any idea's???? Vaccum leak maybe??? Thanks!!!!

Your AC is flipping on and off. It's probably a pressure drop in the suction line. There's a clog in the AC system somewhere. On the receiver is an electrical connection. (Black cylinder) by the passenger side fender. Unplug it and the AC won't come on until you get it fixed.

-Mark

These cars have a known issue of vibration from the engine when the A/C or Defroster is on. The exta load from the compressor makes the engine shake a little and sucks a lot of power.

Ford released an updated motor mount to help with the vibration, but it is considered a "Normal characteristic" of the I-4 engine.