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Vacuum leak near the brake pedal?


jkufen

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In my 86 B2, last night I was driving and I heard a noise, a psssssssssssssssssss, sound coming from near the brake pedal. I thought it might had been a leaking brake hose or something and I mashed the pedal and it didn't seem to be loosing pressure or anything. The weather has been crappy so I haven't been able to check it out but any ideas what could be in that area to cause it. I know it's near the pedal because when I put my foot on the brake and mash a little it sounds like my foot is blocking it. I haven't notice any difference in how the truck runs so I don't know what it could be. Thanks for the help!
 


UrbanRedneckKid

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Vacuum brake booster. If it is vacuum.

There's a big hose that goes into the booster, typically on the front of it behind the master cylinder reservoir.

Pull it off and cap it, with the engine off. Start the engine, See if your noise went away. If so replace the booster.
 

Tedybear

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Check the rubber grommet on the check valve. Mine did the same exact thing and it turned out to be a split in the grommet at the 6:00 position.

S-
 

jkufen

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If it was an issue with the brake booster would there be an other issues I would notice? Also would I still have good brakes if the booster was failing? Thanks
 

wildbill23c

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My 84 B2 is doing the same thing, its the grommet on the end of that hose on the brake booster that is bad causing the vacuum leak. Don't replace the booster unless it is in fact failing you'll waste your money, I think there should be a replacement hose for that if I'm not mistaken.
 

UrbanRedneckKid

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If it was an issue with the brake booster would there be an other issues I would notice? Also would I still have good brakes if the booster was failing? Thanks
Depends how bad the leak is. Usually they are diagnosed and fixed before you feel a loss of power assist/ or have a hard pedal.
 

wildbill23c

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If the brake booster is failing you will have a loss of the power brakes meaning the brake pedal will be harder to press to get any braking effect, you won't lose your brakes, it would just be like driving without power brakes, meaning you have to apply a heavier amount of force to the brake pedal to stop. If you are having those symptoms you will have to replace your brake vacuum booster.
 

70roadrunner

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if you have cruise control there is a vaccuum switch at the pedal to cut the the c/c. the biggest bummer is the hose is barely accessable without pulling the dash. i hope this helps
 

PlumCrazy

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if you have cruise control there is a vaccuum switch at the pedal to cut the the c/c. the biggest bummer is the hose is barely accessable without pulling the dash. i hope this helps
If your cruise doesnt work anyway, just cap the line in the engine bay and call it a day.

Sent from my DROID RAZR using Tapatalk 2
 

jkufen

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Yeah i have cruise control and it doesn't work. I was half tempted just to pull everything out and clean up under the hood. Hopefully soon I will get a good day to check it out and see what the issue is. I hope I just cracked the check valve or something with my big clumsy feet. I drove it again last night to go pull out a buddy that was stuck and the noise is still there and the brakes work fine so I am guessing that it is just a cracked line and check valve.
 

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