Brake Problem

[Paul Masley]

I have finally figured out the brake pedal drop in my '02 SE. There is a sensor on the left rear axle bars for ride height and if the rear brakes are not adjusted tight, the pedal will feel like it will hit the floor.

The problem I have now is actually "No Brakes." On a cold startup, you had better have the dang thing pointed in the direction you want to go, for at least 1/2 block or you cannot stop it. I have had the rotors turned on car as Ford states, replaced the titanium pads (OEM), turned the rear drums and replaced the rear shoes with OEM's. The car has a full pedal. Just for another thought, they have also been bled. The car has 64K on the odometer

Once the car have been moved at least three hundred feet the brakes work, but seem to be a 50% instead of 100%.

Any ideas? I have ran out of them.

[FlamingTaco]

I have not seen the 2002's, but up until 96, the Taurii/Sables had a valve, not a sensor, on the rear suspension to limit brake line pressure based upon rear ride height. If your "sensor" had steel brakelines going to it, that's what it was.

As for the pedal going to the floor, yes, it will do this until you pump enough fluid into the line to put the pads up against the rotor. This should only happen upon reinstalling the calipers after the piston had to be pushed into the caliper, as when one does a brake pad and rotor job.

Is the pedal very hard to press upon cold startup? If so, you have a problem with your brake booster or the vaccuum used to provide the assist.

If the pedal goes to the floor during a cold startup, does it firm up if you press it several times? If so, you have a slow leak somewhere after the master cylinder.

Does the pedal go nearly to the floor all the time? if so, you either have air in the line or a master cylinder with worn piston seals.

Good luck!

[Paul Masley]

It is a sensor style valve. It is on the upper driver's side arm and yes, steel lines are going to it. I traced the dropping pedal and out of adjustment rear shoes to that problem and now have that one under control. Everytime I have the oild changed, I have the mechanic to tighten up the rear shoes. This was also causing the sensation of the pedal going to the floor.

The pedal is fine upon cold startup, there just is not any braking force until it seems that the brakes warm up. The booster and assist has been checked and is within specs.

I have come to determine that it is not the master cylinder, booster, water or air in the lines or leaks. It is like the clamping effort of the pads and shoes just is not there. I drove an '04 yesterday. The brakes on that car will throw you through the windshield if you hit them as hard as I have to in mine. The pedal feels the same, just the braking effort (clamping) is quite better. The '04 would just about stand itself on it's nose to stop. It was setup exactly the same way as mine, disc on the front and drums on the rear.

Dang, I am at a loss at this one. It is like the effort is being sent but not applied.

[FlamingTaco]

Originally Posted by Paul Masley

It is a sensor style valve. It is on the upper driver's side arm and yes, steel lines are going to it.

If you mean that this is a load-sensing valve, then, yes, that is what it is. It's just not an electronic sensor of any type.

I traced the dropping pedal and out of adjustment rear shoes to that problem and now have that one under control. Everytime I have the oild changed, I have the mechanic to tighten up the rear shoes. This was also causing the sensation of the pedal going to the floor.

Yeah, it's standard practice to adjust the rear brake bias mechanicm anytime you fool around with the brake fluid on vehicles with drum brakes.

The pedal is fine upon cold startup, there just is not any braking force until it seems that the brakes warm up. The booster and assist has been checked and is within specs.

Do you have the proper heat range pads on the car? If everything else if fine, and proper pressure is being applied to the pads, then maybe you were given the wrong type pads, or really junk pads. Did you bed them in properly? Some pads will do this until they get well bedded in.

[Paul Masley]

Like I said, all parts are Ford OEM replacements. I just cannot figure out why the brake effort is so high.