Soft brake pedal

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NickSuzy
E30 Zone Newbie
E30 Zone Newbie
Posts: 75
Joined: Sun Apr 15, 2012 11:00 pm

Post Mon Sep 03, 2012 4:15 am

Hi All,

Am just in the process of getting the E30 roadworthy and it has got a softish brake pedal. Just for clarity it is an 86 325e auto.

I have bleed new fluid through the system as it was about 20 years old. This has not improved things but is just for peace of mind.

When the engine is off the pedal is good with only a couple of inchs of travel. When you start the car the pedal travel increases to approx half distance.

When driving the car seems to dip on the rear when braking. The fronts are working but just not as sharp ar they should be.

I am thinking that it is the servo, what are your thoughts.

any help is greatly appreciated.

Cheers Nick
Grrrmachine
E30 Zone Wiki / Team Member
E30 Zone Wiki / Team Member
Posts: 8043
Joined: Sat Feb 09, 2008 11:00 pm
Location: Warsaw, Poland

Post Mon Sep 03, 2012 6:22 am

Taken from the Wiki:

"To check the condition of your servo, pump the brake pedal a few times with the engine off to get rid of any vacuum in the the servo. Then press your foot on the brake pedal and hold pressure on it as you start the car. You should feel the pedal drop a bit as the vacuum builds. If it does not you may have a vacuum leak or other servo problem. "

http://www.e30zone.net/e30zonewiki/index.php/Brakes