Vaccum Pump Pressure?

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Jan 22, 2010 | 07:38 AM

#16

Cuda_jim

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Joined: Oct 2003

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From: MICHIGAN

Quote:

Originally Posted by 91dirtydiesel

id take my brakes being soft all day compared to having to pull the brake pedal back up with my foot like i do. any one know how to fix that?

My guess is the master cylinder.......the return spring is broke or it's just hanging-up internally. Take a look for binding in the pedal pivot too.

Jan 22, 2010 | 04:39 PM

#17

tjbeggs

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From: Silver Lake Dunes, MI

18 in hg vacuum or more more is spec for the vauum pump. If you have a low pedal then vacuum is NOT your problem. Your rear brakes could be out of adjustment, ABS valve is bad, Master cylinder is bad, or you have a leak. Most common cause is rear brakes out of adjustment. For a test use a pair of vise grips a adjust them so they just clamp the rear brake hose off then hit your brakes. If its still soft then get two more sets of vise grips and clamp the front hose too. If its still soft then you either have a Master cylinder or ABS valve issue.

Jan 22, 2010 | 05:28 PM

#18

wheelie31

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Joined: Jan 2005

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From: pennsburg Pa

is there a way to just test the ABS actuator? since the brakes are fine and the master cylinder is withen 1 year old.

Jan 22, 2010 | 05:39 PM

#19

Action4478

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Joined: Aug 2006

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Quote:

Originally Posted by wheelie31

my brakes work there just squishy and pedel goes done pretty far, I bleed them a couple times, I have worst luck with the brake system i put all new lines on new brake cylinders brake booster and master cylinder all at once last year, and still have problems,

You still have air in the system .. maybe bench bleed the master cyl first

Jan 22, 2010 | 05:40 PM

#20

Action4478

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Quote:

Originally Posted by 91dirtydiesel

I have bad luck with brakes too. My current problem is that my pedal wont return without me pulling it back up with my foot. I hate brakes lol

You need a new master cylinder ....

Jan 22, 2010 | 06:01 PM

#21

paddler

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Joined: Dec 2002

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From: Columbia, MD

Bad Vacuum = HARD brakes

If the vacuum system is bad, you get no power assist, and have to push the hydraulic fluid with only your strength. Good hydraulics and bad vacuum will feel VERY hard and pedal will move very little. Do a double-leg-press on the pedal to get stopped (eventually), but you won't bottom out the pedal.

Really soft pedal suggests good vacuum (pump, lines, booster) but squishy hydraulics.

Sounds like your problem isn't vacuum.

Jan 22, 2010 | 10:33 PM

#22

tjbeggs

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From: Silver Lake Dunes, MI

Quote:

Originally Posted by wheelie31

is there a way to just test the ABS actuator? since the brakes are fine and the master cylinder is withen 1 year old.

Have you adjusted the rear brakes up correctly? Take my advice by clamping brake lines and report back. It is testing and will keep you from spending money that won't fix your problem. Trust me I have been down this road about 100 times....2 times this week.