Check the brake fluid, but if it's up it's probably a problem with the brake "master cylinder". With the vehicle at a stop, in park, step on the brakes to see if you can repeat the event. If the brake pedal goes to the floor, release it and step on it again. That may allow fluid back into the master cylinder and give you brakes briefly. If the master cylinder is bad, do not drive the vehicle until you have either replaced the master cylinder yourself and properly bled the lines, or had a qualified mechanic do it for you. What you're describing is a potentially dangerous situation. What size shoe do you wear? You are stepping on the brake and gas at the same time. This happens to me in my 97 Mountaineer if I'm not careful to slide my foot all the way onto the brake pedal. I can't even drive the car with big winter boots on.
The Mercury Mountaineer has hydraulic brakes, not air brakes.
Disc brakes ( with small brake shoes in the back of the rotors for your parking / emergency brake )
4 wheel ABS brakes are standard on the Mercury Mountaineer in 1999
The brakes on the Villager are as straight forward as the brakes on a 1965 Mercury. Only normal brake tools are required.
If the ((ABS)) Light is on then it's a good thing indicating that the Antilock brakes sensor is in good condition. I too have a 2002 mountaineer
It probally is the transmission or your brakes could be slipping.
Take brakes off and then remove 3 bolts from back of spindle and slide it out. easyest I ever did
disc brakes
Check into the ABS pump or module ---- I would say the pump
the cost of new brakes is irrelevant.... However, what you have to pay is important and its a lot if you take it to the dealer.
Inertia. A body in motion will remain in motion unless acted upon by an outside force. The motion of the bus is stopped by the brakes. The person inside keeps moving as it is not being braked.
A 1991 mercury topaz has drum brakes on the rear wheels.