Ford brakes: Mystery erratic low pedal

18 years ago

My sister is the owner of a 6 year old Ford Escort,automatic, low miles..

Recently, several times now,The brake pedal(upon application) has been lower than normal... at all other times it is normal and the brakes are otherwise good in all respects...

Seems as if the front or the rear brakes are not always self-adjusting correctly...I test drove this car today and found nothing wrong with the brakes other than a unadjusted hand brake...

This is strange.

Comments (11)

cowboyind
18 years ago
I've also seen this sometimes occur from having air in the brake lines.
gary__
18 years ago
If it's intermittent I'd guess it's the master cylinder. If it's a 1 pump and it's good every time for a while I'd guess it's adjustment.
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earthworm
Original Author
18 years ago
About 4 months ago she paid about $ 200 for new brakes all around ( 6 years old ,less than 35K miles )..
This erratic behavior has occured 2 to 3 times within this past week...
I drove it yesterday - all OK but for a poorly adjusted handbrake..
Today the dealer checked it ($30) - all OK . My sister forgot about the handbrake.
I guess this is the normal dealer car service of the 21st century...
earthworm
Original Author
18 years ago
Another thought on this - the car('99 Ford Escort 34K miles) has hundreds of $$$dollars of new brakes installed 4 months ago.

Why ??

I believe that at times the front caliper piston seal is sticking - particularly during light applications...
Thus it is not properly returning to within 0.05 of a mm of the rotor all of the time.

My sister may be a brake pedal rider - I have seen many, many drivers do this..

And I suspect the light applications have something to do with this - either that or Ford quality is not that good..

The clearances at the caliper and pistons has to be most precise..
Also, no surprise if the answer is not in "Motor" magazine...
majorxlr8n
18 years ago
Earth - check the rubber, flexible brake lines for swelling. Not very common, but I have seen this condition before...

Marty
earthworm
Original Author
18 years ago
Good point, Major, and I did think of this..
This Ford is but 6 years old, I would not consider that to be too old at all.
The Saab and VW flex brake lines would normally last at least ten years or the life of the car...

Here is one for the books, and I am not making this up.
Back in the early 70s, during the times of the Mazda rotary engines, I owned a RX-2 model..
In the maintenance manual the car-maker suggested to renew the rubber brake hoses every 24,000 miles !!
Unbelievable !!!
Of course this was never done.....no need existed...
gooseberry_guy
18 years ago
Hey, EW,

The engine was only good for 40K, so anyone could have slid by for another 16K, without a need for changing the lines.

The RX-2 I had, sat for a few weeks before I sold it. A disc pad actually rusted tight to the rotor, and when I took it out for a drive, it ripped the pad from the backing plate. I couldn't figure out right away why the pedal went to the floor. I needed to pump up the pedal to get it back up. After I parked the car, I noticed the pad on the ground, and could then figure it out.

By the way, mileage on mine with the 4 speed, was about 14 in the city, and 18 on the highway. Pretty bad for a time when the price of gas started taking big jumps.

GG
earthworm
Original Author
18 years ago
Yeah - and GM was foolish enough to buy into this loony rotary engine "technology"..one of the many steps in their downfall...
I think now the solution with the erratic Ford brakes is a version of the Italian tune up !
jemdandy
18 years ago
If you have shoe brakes in the rear, check out the self adjusters therein. These may be jammed and need to be cleaned and lubricated.

After freeing up and cleaning the adjusters, re-assemble the drums and ajust the shoe brakes. Then check the fluid resevoir on the master cylinder and top off if needed.

After the first application of the brakes, the shoe brakes may not be returing fully and the next time you apply the brakes, all seems well. But, with road shocks, the shoes may drift all the way back to their stops and then it will take extra pedal movement to push them against the drums.

Also, you may have a parking brake cable that is draging in its housing. It should be free to slide. If not, replace.

While you are into the brakes, inspect the return springs. if these are in bad shape, replace.
Socalinspector
18 years ago
WOW ! Earthworm can't figure out a simple brake problem, and THIS car is in your possesion. Yet you can give answers to people with problems much more technical ? This just proved my point.
Steven Barker
8 years ago
Bad master cylinder ? Good place to start looking. That's where I would start first, if it was my car.

Ford brakes: Mystery erratic low pedal

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Ford brakes: Mystery erratic low pedal

Comments (11)

cowboyind

gary__

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