Help! Ford Focus 8xs in shop/8 weeks. They think I'm crazy; they say "it ran fine for us...again."

ford
brakes
transmissions

#1

I’m not crazy. I’m not crazy. This had been my mantra to the service center.

Click to image of that nutty lady rushing again into Ford. I fling open the door and shout out the name of any technician since I already know them all. “Jon, it’s doing it right now! I swear! Hurry, hurry!” or “Chris! Hurry, hurry before it stops!” I drag them out so they can witness me pouring water on the front tires or shove them in the front seat so they can drive it this minute, right now, even though I’m pretty sure when they touch it, it will run perfectly again.

2005 Ford Focus. 91,000 miles. Regular oil changes & maintenance. Last lrg maintenance pkg in Feb, everything flushed. No problems at all with this car until April 2011, (although that was the alternator & it was replaced.)

Regarding the mystery problem: in the last 8 weeks they have replaced the brake pads 4 times, rotors 2xs, calipers 2xs, the brake lines have been replaced once but that may increase by tomorrow and I have had 3 diagnostic tests on the transmission which yielded nothing & the master cylinder was checked and okay. (Tomorrow is another D-Day. I think they’re giving my car back again.)

Here’s what it’s doing still & getting worse
(Note: this doesn’t happen EVERY TIME you drive it, but it happens sometime EVERY DAY -throughout one full trip from here to there, distance doesn’t matter.)

Immediately on pulling out, I can tell if this is going to be a trip where it does this (by the feel of the brakes and how the accelerator is responding)
You can hardly push the brake pedal down, it will be so tight (the longer you drive it, the tighter it gets)
It loses power when accelerating and eventually will slow down instead of speed up

Accelerator will not respond and car will rev into another gear; it can stay there for as long as 5 minutes, getting louder and louder till you’re not sure if you’re going to explode or shift.

Or it will rev for 15 seconds, give up, go back to the quiet not-accelerating, then repeat this process over and over until you’ve reached your destination or pulled over because car just won’t accelerate any more.

Sometimes you can put your foot all the way to the floor on the accelerator and it will still slow down
It will slow and stop on it’s own w/o touching brake if you’re not accelerating

At light or stop sign, will crunch to a stop.
After light or stop sign, it crunches to a go.

I had someone ask me if I was sure I was in “Drive” when it happens. Although I had a lot of clever comebacks for this, I did double-check and yes I am.

‘Punching’ the brakes makes no difference
Backing up at least 20 feet does not make a difference.

Now it’s shaking again, when I go over 45mph. It will do this for several minutes and then just fade away. The shaking part is the only thing that goes away on it’s own in the course of one of these trips.

After it does this, you get to where you’re going & give it at least 15 minutes and/or pour water on the wheels, then it will start up again and work perfectly. The working perfectly part seems to happen every single time it touches the parking lot at the service center. All test drives are great; “it worked fine for me, are you sure you’re in Drive?”

Help?

P.S. I know this is Car Talk, so please forgive my non-car-speak. Mostly I make noises when I discuss this; words are actually progress.


#2

Do you pour water on all four wheels’ brakes? After this experience, is one wheel hotter than any of the others? The heat would indicate excessive friction from constant braking.

Since there are four wheels, you could try the water treatment on two of the four wheels, and then one wheel, to try to isolate which wheel(s) are affected. If it’s all four, that would suggest a system-level problem; if it’s just one brake, it could be a stuck caliper. But I’m surprised the shop wouldn’t have found that…


#3

Thank you so much for the suggestion!

So far, in the beginning, it was just the right front wheel. There was a smell like something was burned up and it was definitely hotter than the left one. Last week though, you could feel the heat coming off of both of the front wheels and I poured water on both.

I only did the front two since it’s a front wheel drive, but when I get it back today and it does it again (*sigh,) I’ll try it on all four. Thank you! :slight_smile: Anything, anything helps.


#4

Do you have ABS? Have the rear brakes been serviced lately and are the rear brakes disc brakes?


#5

My theory is that you have a bad brake booster.

When you’re normally sitting still in park, brakes off, vacuum from the engine is distributed evenly to the front and rear surfaces of a diaphragm located in a canister mounted on the firewall, just behind the brake master cylinder. When you press the brake pedal, a rod behind the lever pushes a diaphragm inside a canister such that the engine vacuum becomes sealed in the chamber foreward of the diaphragm and the back side of the diaphragm becomes vented to ambient. That vacuum pulling that diapphragm helps you push the rod going into the master cylinder. It helps you apply the brakes.

I suspect that what’s happening is that the booster is defective in a way that is allowing the engine vacuum to constantly pull the brake rod forward, creating drag on the pads and heating the fluid up to where it’s exascerbating the problem.

At this point I really think the booster should be looked at. Once the problem is corrected, I’d suggest that the brake rotors and pads be looked at for wear, scoring, glazing, and lateral runout, and that the fluid be flush out with new fluid. The old fluid may have boiled.

It might also be prudent to change the flex lines at the calipers. Heat can damage the linings and cause them to swell into and block the lines.


#6

I concur with Mountainbike’s theory.

In addition to the brake booster applying the brakes without you touching the brake pedal, the vacuum problems that are part of the situation are causing the engine to be non-responsive on occasion. With any luck, simply replacing the brake booster will resolve all of the problems.


#7

Wow! Thank you so much. I had to read all of the comments several times and look at pictures while I was reading them, but I think I get the general idea. All this time they replaced pads, rotors, calipers, lines…and with my not-understanding, I thought this must be the entire brake system. Thank you so much. I will be mentioning brake booster to Ford and now have a little knowledge to back it up. Thanks again!


#8

If you have ABS, the ABS system could be causing this.


#9

By the way, I apologize for not mentioning it sooner but there’s a simple way to test for this. When it’s happening “every day”, disconnect and plug the vacuum line to the booster and see if the problem disappears. If it does disappear, it’s the booster. Your braking will he hard because you’ll have no assist, so be prepared, and just test it this way, don’t take any trips like this, but the test will work.


#10

I think Mountainbike is on the right track here. Call me if you have any questions. Your and Davs friend, Rod.