Continental Stuters

Hi,
I got the auto recently and now when i drive it after about 10
minutes, when i stop at a stop light for example while pushing on the brake (as normaly you do with automatic cars), the car seems to hesitate repeatedly every few seconds. While driving there is no
indication of hesitation and car runs fine besides that.
I ran the system check and said its all ok.

Does anyone know whats going on?


Thanks in advance,
Jerry

Hi,
-- while pushing on the brake -- the car seems to hesitate repeatedly every few seconds. --
Does anyone know whats going on?


Sounds like a vacuum leak at the power brake booster. Could also be a defective (torn) diaphragm inside the brake booster.

Sounds like a vacuum leak at the power brake booster. Could also be a defective (torn) diaphragm inside the brake booster.

Thanks for the reply althought I don't think its coming from the brakes, because i notice the engine hesitating and i don't feel anything on the brake pedal.

Thanks for the reply althought I don't think its coming from the brakes, because i notice the engine hesitating and i don't feel anything on the brake pedal.


That's typical, you won't feel anything at the pedal. The hesitation or stumbling is caused (in my diagnosis) when vacuum escapes from a defective booster.

Try this if you want to eliminate my diagnosis as a posibility to your problem:

Find the vacuum hose connected to the brake booster. It's larger than 3/8" in most cases.
Disconnect the hose, plug the end so no vacuum will escape from the engine, then run your situation again to see if the problem still exists.

Cheers

That's typical, you won't feel anything at the pedal. The hesitation or stumbling is caused (in my diagnosis) when vacuum escapes from a defective booster.

Try this if you want to eliminate my diagnosis as a posibility to your problem:

Find the vacuum hose connected to the brake booster. It's larger than 3/8" in most cases.
Disconnect the hose, plug the end so no vacuum will escape from the engine, then run your situation again to see if the problem still exists.

Cheers

WOW, you are good, i did notice this time that it was related to the brakes. i don't have a way to work on the brakes, but sure seems u are right.
thanks alot, here i go to the shop :)

-Yariv

Hey Yariv --

I'm happy to hear you've diagnosed your hesitation problem :)

Before you run off to a mechanic, be sure all the Vacuum lines connected to, and around the brake booster are not leaking.

There can be an old hose with a bad connection that'll give the very same problem as a bad brake booster.

Also, where the main vacuum line connects to the brake booster, it normally connects to a plastic check valve << that plastic check valve sits in a rubber grommet connected to the brake booster >> if that rubber grommet is dry/rotted/brittle/cracking, vacuum can escape from there as well and cause the symptoms you describe.

I only mention these alternatives, 'cause they may be a problem you can fix yourself.

Also, I'm still fairly (without being there) positive it's a bad brake booster, and FYI -- their relatively easy to replace with basic mechanics tools. You didn't mention which year your new Conti is, but their all pretty much the same.

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