You could either be in too high of gear or your (if manual)clutch might be going out.
Belt
Fuel Pump problem or clogged converter
Check the catalytic converter. They get plugged and cause the vehicle to lose power.
Gravity.
I just had my 93 Aerostar 3.0 in for this same problem. My MAF sensor was plugged. Once cleaned, it now runs fine again.
could possible be because there are gravity fed and the motor is gettin choked of fuel
energy going to a phone will make it lose power so its going place to place
You may have a blown head gasket.. Check the coolant overflow for oily, black residue.
probably going to lose your steering
Not a good idea, you will lose the power steering and power brakes.
It loses power because going uphill is harder then going downhill therefore causing it to use more gas and then making it lose power bit by bit.