It sounds like you are low on refridgerant, i would have your A/C lines inspected, and maybe try to recharge it, could also be a bad A/C pump.
the load of the AC compressor slows the engine
The 1998 Ford E3 50 low pressure air conditioning port is located on the air conditioning compressor. The low pressure port will be on the right hand side of the compressor.
why wont the ac compressor shut off stays on on all settings
It controls the elctrical clutch on the compressor.0
The idler pulley is between the alternator and the A/C compressor.
Most of the relays for the ford escort are located under the hood in a black box with white labelling on it. Also check your underdash fuses. If this doesn't repair the problem, then you might have to replace the air compressor, as they sometimes do set up. The AC compressor relay, and the AC wide-open throttle cut-out relay are in a box under the air cleaner. It is called the multi-function relay. Try tapping on it while the AC switches are on and see if it will start to work.
The 1998 Mazda 626 low pressure port for your air conditioning system will be on the top of the air conditioner compressor. The low pressure port will be on the left-hand side of the compressor.
You can recharge your 1998 Mercury Mystique air conditioning system through the low pressure port. You can find the low pressure port on top of the air conditioning compressor.
Connect your Freon bottle to the low pressure port on your 1998 Chevy S 10 Blazer air conditioning compressor. Discharge the Freon into the compressor. A recharge kit will make this process quite simple.
Both high and low service ports are located on the top of the a/c compressor manifold assembly......
brake diagram for 1998 ford escort
About 5 Liters according to the manual. You can never have too much oil. Nice wheels