Backyard (or pro) auto mechanics: Can you figure this one out?

Miscellaneous and Personal Stuff I Must Share
1

I have a 2002 Hundyai Elantra with close to 140,000 miles on it. It’s a bit of a beater by now. I mostly use it to drive the short distance to and from work and to run a few errands around town.

A couple of days ago, I drove to a client’s office for a brief meeting. All was well with my car. But when I started it to leave, I noticed that the brake pedal was difficult to push down. Instead of going all the way down to the floor, it was the opposite problem — it would only move a short distance before stopping. It also seemed more difficult than normal to take the car out of Park and put it in Reverse.

However, I did succeed in doing this. When I started to drive, I noticed that the car was moving, but very slowly, and not responding to giving it more gas. It wouldn’t go out of first gear, and just barely moved forward. The brake pedal was the same as before; the brakes operated, but the pedal couldn’t be pressed down very far without meeting a lot of resistance.

I drove for a short distance this way, and noticed a sort of burning odor coming from under the hood. At this point, I stopped the car and looked under the hood (as if I would be able to tell much from doing so!). The transmission fluid and other fluids seemed OK.

I was afraid to drive it any further, so I called AAA and got a tow to a small, old-school mechanic’s garage. I trust this guy and have used him several times in the past.

As they were backed up with other customers, I had to leave the car and get a ride back to work. The next day (yesterday), I got a call from my guy. He said they started the car up and drove it a considerable distance on several separate occasions without incident. It responded completely normally. They checked all the fluids and also put the car’s computer on a diagnostic, which showed nothing amiss.

He was busy again today when I picked the car up, so we didn’t have any time to indulge in speculation as to what could have happened.

But that’s my question: what the hell did happen? It seems obvious that the business with the brake and the difficult of taking the car out of park has something to do with the interlock system. But how would that affect the actual drivability of the car? And how could this very real problem (I didn’t imagine it, I assure you) spontaneously cure itself?

Any and all ideas are welcome. I’m hoping against hope this problem doesn’t recur just as spontaneously!

2

Maybe the Brake pads pressing down and burning? The pedal could have been stuck and the brakes were partially engaged. That would explain why the car didn’t want to move.

Did you leave your parking brake on?

3

Definitely not. I virtually never use the parking brake, and would have had no reason to put it on where I parked.

But your explanation would make sense if the regular brakes somehow got engaged and didn’t release. How that would have happened, though, I have no idea.

4

Popular Mechanics did an article on sticky breaks. Several things could be causing the problem. Sometimes the calipers are the culprits. Google sticky brakes for more articles.

5

The more I think about it, what you described is probably what happened.

I wonder if the act of winching the car up to be towed somehow “unstuck” the brakes. The problem was still very much there when I first stopped the car. At some point before calling AAA, I started it up and tried to take it out of gear. As I recall, the pedal still barely moved and I couldn’t get out of Park at all, and didn’t want to force things any further.

In retrospect, I probably should have tried to start up the car once it was deposited at the garage. But it’s the kind of small place where the owner and his one or two mechanics are always busy. He wouldn’t have had the time to take a look at it with me then.

6

The pedal engaging really high is a classic symptom of a stuck parking brake on a car with rear drum brakes (which I assume this has.) What happens is that the parking brake cable pulls at the bottom of the brake shoe to wedge it against the drum, but this also moves the top of the shoe much closer to the wheel cylinder. So when you step on the normal hydraulic brakes, it takes less movement of the master cylinder (what the pedal is attached to) in order to extend the wheel cylinders as far as they’ll go.

I suspect the interlock issues are just because the interlock device depends on the pedal engagement and the above issue was preventing the pedal from going down as far as it needed to.

To fix the problem, a good place to start would be to check the parking brake cable to make sure its not binding or rusting to the body somewhere. Popping the drums off and cleaning everything and lubricating the parking brake actuating hardware would also be a good idea.

7

Sounds a bit like the engine computer went into “limp.home” mode, where everything works but only as much as needed to get off a highway or a few blocks home.

8

Flexible brake hoses can sometimes deteriorate internally stopping the flow of brake fluid back to the reservoir. As the brake, probably just one, is already pressurized, you wouldn’t need to press down the brake pedal as much to get the other three brakes working. Plus the brake with the back flexible hose would be grabbing all the time and could overheat after a few miles.

Anti-lock brakes? It’s possible that something could go worn there preventing properly pedal actions.

Bad vacuum booster is a possibility. Pump the brakes about a dozen times before starting the car. That should empty out the vacuum reservoir for the brakes. Then with you foot on the brake, start the engine. You should feel the pedal fall away an inch or so. If not there could be a vacuum leak in the brake booster or something else is messing with the brakes.

9

Many thanks to all of you who’ve weighed in on this.

In retrospect, the explanation of the brakes locking seems painfully obvious now, and we also have a a couple of plausible theories as to what might have caused this to happen. (And I’m going with my theory that lifting the car with the tow truck was what caused the problem to spontaneously cure itself!)

In any case, I’ll know what to do — and more important, what not to do — if I ever get the resistant brake pedal symptom in the future.

Thanks again.

10

I would almost bet money on the parking brake being applied.
It explains all the symptoms high hard pedal
Low power
Burning smell
Hard to get out of park

11

Well, you’d lose the bet. I know for absolute certain I did not apply the parking brake. As I said, I almost NEVER use it, and there would have been no earthly reason for me to apply it at the client I visited, as his parking lot was on a flat surface with no grade.

Somehow, my brakes did lock up, but it was not because of the parking brake. GreasyJack’s and JerrySTL’s scenarios are more likely explanations.

12

::: shrug:::
Wouldn’t be the first time I’d been wrong, but a couple things to consider. GreasyJack’s scenario requires you to either apply the e brake or snag the cable on something to activate the system before rust could hold it in place.
JerrySTL’s scenario with the brake hose is possible. I’ve never seen a brake hose that has failed like that but I have heard of them. The problem is how/why did it fix itself?
If the car was not pulling to one side it would be the flex hose to the rear axle
It is possible you applied the e-brake without realizing it ( I’ve seen this several times) on a pedal operated brake by hitting the pedal by accident or on a lever dropping something between the seats and pulling up on the lever to fish it out.
I just thought of one more possibility if the master cylinder itself is sticking internally it could act the same as a bad brake hose, but again how did it fix itself?

13 
I go along with Rick on this. People who never use the parking brake are the ones who run into this problem most often because they don't even consider checking the brake when they have a problem. I never use mypark brake either but on a few occassions for no apparent reason i have and the results were just as you descirbed.
14

I have had people drive in with the exact complaints that the OP has. When I have pointed out the brake is on they swear it isn’t.
Best e brake story ever. Car is towed into a dealer. Front wheel drive car. Driver has two complaints

  1. Car is low on power
  2. Both rear tires were flat. Customer had driven the car with the rear wheel not turning due to the e-brake being fully on. I have no idea how many miles it took to wear the tires all the way through till they popped.
15

The thing about almost never used parking brakes is that the cables seize up from non-use. If you used it a week ago then they may have partially stuck on. Now if this happens on a car with rear drum brakes you may actually make the problem worse days later by backing the car up because that’s how drum brakes adjust themselves. Every time you hit the brakes while backing up it spins a nut that tightens the assembly. I’m not saying this happened but just throwing out one of those head scratchers that are hard to spot.

With that said it’s not unusually for calipers to seize up. This clearly seems to be a brake problem so the time to look them over is before it happens again.

16

If it happens again before you get to a mechanic then stop and use your senses. You can smell which brake is getting hot and you can feel the heat radiating from the rim. Don’t be grabbing any parts, they get seriously hot.