i have a 1994 F150 302 5/0 liters and i need your expertise to solve my problem. last monday june 20 2011 we are headed for our holiday. the truck was fine for over 200 hundred kilometers when check engine appeared on the dash board. the truck run slow and could not negotiate highier elevation the most i can travel was maybe 5 to 10 kilometers an hour. i reached the nearest city and went to the truck repair shop. the mechanic did a series of engine test and found out the Air M A F is the problem. In order for us to continue our journey the mechanic disconnect the Air M A F harness and said that we will be able to drive the truck with no problem and informed me to replace the Air M A F as soon as i reached big city. i bought a Air M A F and i replaced it by myself and connect electrical harness. the truck run fine for a few kilometer and then lost power. the truck run very slow. I stopped the truck and disconnect the electrical harness and the truck run fine. so to all expert mechanic kindly tell me where is the problem. thank you