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Leaky brake booster?

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Old 02-10-2012, 04:03 PM
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Default Leaky brake booster?

When I push the brake pedal down I hear air coming out of some place. Every once and I while if I put my foot on the brake when I'm in park my RPM's go up a little. This is my brake booster leaking right? Is there any way to fix it without replacing the brake booster?
Old 02-10-2012, 04:10 PM
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Not that I am aware of. If i remember right, mine was about $60 and came with a new master cylinder. Took about an hour to do.
Old 02-10-2012, 04:19 PM
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Originally Posted by Eugene Jeep
Not that I am aware of. If i remember right, mine was about $60 and came with a new master cylinder. Took about an hour to do.
That is indeed my brake booster though, correct?
Old 02-10-2012, 04:24 PM
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Depends, there may be nothing wrong with your booster.

what does the pedal feel like?

Power brakes make noise out of the booster, at least on any vehicle I have owned you will here a woosh from time to time. This is any vehicle Ive owned straight off the line or used.
Old 02-10-2012, 04:24 PM
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sounds like it to me! Without being there to hear exactly what the sound is, i can't be 100% sure, but i can tell you mine did the EXACT same thing. The hiss is you loosing vacuum (most likely going back into the motor, causing RPMS to spike a little.)
Old 02-10-2012, 04:40 PM
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Your RPMs go up a little bit because you are putting a small amount of load on the system. I agree with Stockli on the fact that all vehicles with power brakes make a sound when you apply the brakes. You probably have just never noticed it before. There is a chance there is something wrong but from what I can tell everything is working fine.
Old 02-10-2012, 05:12 PM
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Originally Posted by stockli
Depends, there may be nothing wrong with your booster.

what does the pedal feel like?

Power brakes make noise out of the booster, at least on any vehicle I have owned you will here a woosh from time to time. This is any vehicle Ive owned straight off the line or used.
Well to fully stop I need to press down fairly hard, that's another reason why I think it might be the booster. Is there a simple way to check for a vacuum leak?
Old 02-10-2012, 05:12 PM
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Originally Posted by DrShaggford
Your RPMs go up a little bit because you are putting a small amount of load on the system. I agree with Stockli on the fact that all vehicles with power brakes make a sound when you apply the brakes. You probably have just never noticed it before. There is a chance there is something wrong but from what I can tell everything is working fine.
Hmm. Okay I just won't worry about it for another few months
Old 02-10-2012, 06:07 PM
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rpms raise because booster is leaking vacuum so the ecm is adding more fuel replace it
Old 02-10-2012, 06:15 PM
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You can test by pulling the check valve on the front of the booster. If its holding pressure your probably ok, if no pressure then from your symptom of a hard to push pedal the booster is probably shot.

MAKE SURE YOU PULL THE CHECK VALVE, if you just pull the hose it the check valve wont let air in (if its not leaking)

I just dont want to see you replacing a perfectly good booster, its a PITA
Old 02-16-2012, 01:39 AM
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Originally Posted by stockli
You can test by pulling the check valve on the front of the booster. If its holding pressure your probably ok, if no pressure then from your symptom of a hard to push pedal the booster is probably shot.

MAKE SURE YOU PULL THE CHECK VALVE, if you just pull the hose it the check valve wont let air in (if its not leaking)

I just dont want to see you replacing a perfectly good booster, its a PITA
Can you try explaining that one more time. I feel like you kind of said two things that are the same but you said two different things....might be me though.
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