The message to which you are about to reply is shown first. GO TO REPLY FORM



 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

940 low brake pedal 900

posted by  Mike91 on  Sun Jul 29 20:54 CST 2012
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Wed Sep 17 19:52 CST 2014
[RELATED]

1994 940 wagon, 180K, original brake master cylinder, calipers and brake lines.

Recently I realized that the brake pedal can be pushed almost all the way to the floor with enough effort - probably 40 lbs force with the engine running. Front and rear pads are wearing evenly. The braking system has plenty of stopping power, on a dry road ABS can be activated with a hard push on the pedal. In normal driving the pedal only has to be depressed 2-3 inches to engage the brakes and stop the car.

With engine off, the brake pedal feels hard after pushing a couple of inches. However with constant pressure on the pedal, starting the engine causes the pedal to sink several more inches and it gets close to the floor. Turning off the engine, the pedal stays down so the booster is functioning OK with no vacuum leaks.

I just power bled the system with a Motive bleeder - no change. The master cylinder fluid level does not seem to be decreasing over several months. After reading the FAQ, I suspect either the master cylinder or rubber brake lines. The rubber lines all look OK but I havent yet checked for expansion under high line pressures.

Can a master cylinder problem cause the symptoms even though there is no fluid loss ?

Thanks,

Mike

91 740, 93 940, 94 940





USERNAME
Use "claim to be" below if you don't want to log in.
PASSWORD
I don't have an account. Sign me up.
CLAIM TO BE
Use only if you don't want to login (post anonymously).
ENTER CAPTCHA CODE
This is required for posting anonymously.
OPTIONS notify by email
Available only to user accounts.
SUBJECT
MODEL/YEAR
MESSAGE

DICTIONARY
LABEL(S) +
IMAGE URL *
[IMAGE LIBRARY (UPLOAD/SELECT)]

* = Field is optional.

+ = Enter space delimited labels for this post. An example entry: 240 muffler


©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.