PDA

View Full Version : Brake Pedal "Tapping"/"Knocking" Sound - 89 535i


angusbn
10-13-2007, 02:34 PM
When I depress the brake pedal there's a "tapping" or "knocking" sound each and every time. Anything to worry about? There's no problem with the braking power, it's just the noise that has me worried somewhat?

Blair...
e34.535i.sport
10-13-2007, 03:14 PM
I have a 'click' type noise that happens in intervals when i depress the brake pedal, its happened ever since i got the car and i've had no problems with it. The clicking seems to come from somewhere around the glovebox strangely enough. It doesn't worry me at all however as the brakes work perfectly, and the noise is only audiable with the radio off and everything else silent.

Others might be able to offer more advice if there is a problem, but you will need to provide more details - does the noise come from inside the car or outside? Is it more of a knock or a tap? Does it happen only when you press the pedal hard or soft, or all the time?
Barney Paull-Edwards
10-13-2007, 03:15 PM
Your release bearing is on the way out,OR get a friend to operate the clutch and look carefully at the front pulley, if it moves when the pedal is pressed then your thrust bearings are worn,strip down or Wynns and sell it.
e34.535i.sport
10-13-2007, 03:19 PM
Your release bearing is on the way out,OR get a friend to operate the clutch and look carefully at the front pulley, if it moves when the pedal is pressed then your thrust bearings are worn,strip down or Wynns and sell it.

Is this related to the brake problem?
Barney Paull-Edwards
10-13-2007, 04:40 PM
Sorry, wrong post!
myles
10-13-2007, 04:45 PM
If your car is RHD your brake light switch is behind the glovebox. On my 1988 car the brake light switch is above the pedal, but on my 1990 car the switch is behind the glovebox.

Its quite common for the switch to click twice each time the pedal is pressed.
e34.535i.sport
10-13-2007, 05:15 PM
Thats good to know, thought i had problems then Barney! (I've done that before too! :) )

And thanks Myles, mine is 1990 so must be the switch for me.

Any help to you so far Angus?
angusbn
10-14-2007, 08:24 AM
Yes, it's more of a "click" sound coming from above the brake pedal in the dash area EVERY time I hit the pdeal - soft or hard. I'll take the dash cover off today and see if I can pinpoint the cause. Again, the braking power is not impeded.
angusbn
10-16-2007, 07:09 AM
I have a 'click' type noise that happens in intervals when i depress the brake pedal, its happened ever since i got the car and i've had no problems with it. The clicking seems to come from somewhere around the glovebox strangely enough. It doesn't worry me at all however as the brakes work perfectly, and the noise is only audiable with the radio off and everything else silent.

Others might be able to offer more advice if there is a problem, but you will need to provide more details - does the noise come from inside the car or outside? Is it more of a knock or a tap? Does it happen only when you press the pedal hard or soft, or all the time?


The "clicking" sound seems to come from the small diaphram on the firewall that I guess is part of the brake booster (brake servo). Each time I depress the pedal I hear this annoying sound. Doesn't look like it's a separate part but part of the booster. Don't really want to replace the unit since the braking power is OK. Any other suggestions?
DaveVoorhis
10-16-2007, 07:12 AM
Any other suggestions?
Endure. It's normal.