What could be causing my front right brakes to get tight and decrease in speed very rapidly on a Ford Focus 2006 zx4?

Well I’ve been having this problem for a long while now causing me not only frustration but not to be trusted at work for getting there late and other personal problems.

I’m trying to sell the car now , since I can’t find the problem nobody would take the car as it is.

On a normal day it would happen but happens most on a hot day or also when I turn on the air conditioner. I would be driving normally and the car would start slowing down rapidly once I let go of the gas pedal while not pressing on the brake. And then as the problem continues if I try pressing the gas the car would accelerate roughly 30-50 miles per hour and it would sound as if the engine or car can’t handle it since the front right brake is getting tight.

When I let go of the gas pedal while going 50 the car will decrease in speed rapidly to 20mphs and start smelling like burnt brakes.

I’ve had to stop the car several times even on freeways to cool down the brakes.

1. What seems to help is letting the brake cool down and press on the brakes while the car is off. Like I feel the pressure releases or something

2. I’ve changed the brake hose once recently , caliper twice with bolts and everything , I’ve changed the rotor or disk twice as well, including brake pads since either they broke because of the heat or pressure.