1994 Ford F-150 timing

For no reason I can think of the power of the truck has deminished conciderbly. I did a regular tune up plugs cap roter & wires. No help. So I serviced the transmission thinking that may be the problem but no help. The truck starts fine and runs fine but with any kind of load or steep hill it just poops out. I tried to time it but can not find the "spout" wire to disconnect. Hope you can help
thanks