1999 Ford KA overheating

SOURCE: Ford Ka OHV 1.3i Engine

The motor has what is called a positive crankcase ventilation system (PCV - hence the valve). It also has a pipe that goes from the top of the motor to the air cleaner. If your piston rings are well warn, the added pressure that this produces will force a quantity of oil into the air cleaner. A small amount is normal. You are probably losing some oil through the rings as well. The loss of power may be that your compression is low from the bad rings. You can check the compression yourself. They sell compression testers for about 30 bucks. Follow the directions. If a piston does read low compression, squirt some motor oil in the cylinder after the first test. If the reading goes up, that means that the rings are bad.

SOURCE: Ford Ka Fan Belt?

does car have a clutch fan if so stop engine and see if there is any play in fan by trying to move fan blade back and forth if ther is play replace it. also check belt tensioner for excessive play.

SOURCE: Ford ka window switches not working

Check for loose wiring connections behind the door panel on the offending side.

SOURCE: My 2002 Ford Thunderbird is

You most likely have air in the system. These things can be a royal pain to get the air bleed out of the system.
Look back next to the brake booster and you will see a rubber tube with a screw cap in the end of it(this is the heater bleed), also on the front of the intake area you will see a black tube with an allen sloted cap.
Remove the slotted cap and screw the screw cc on the rubber tube. Add coolant to the coolant jug allowing the system to equalize until no more coolant can be added. Add as much coolant as possible to the engine fill( the sloted cap near intake). The heater air bleed will remain open.Replace the engine fill cap.Start the engine and turn the heater to MAX position.Close the heater air bleed when a steady stream of coolant comes from it, during engine idle. Allow the engine to idle for five minutes, add coolant to the degas bottle as needed to maintain the cold fill MAX mark.Reopen the heater air bleed to release any entrapped air and close again. Maintain engine speed of 2,000 rpm for 3-5 minutes or until hot air comes from the heater.Return to idle and verify hot air is still coming from the heater. Set the heater temperature setting to 75° F and allow the vehicle to idle for two minutes.Shut the engine off and allow to cool.After the engine has cooled, add coolant to the degas bottle to bring the level to the cold fill MAX mark. This should have the air out of the system.