my brake booster failed? brake problems.
#1
Drifting
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when i step on the brake pedal it takes way more pressure to stop the car, and when I step on the pedal I hear a hissing sound like air leaking. my brake fluid is full and brake pads and rotors are new.
I just moved to another city with my 944 to go to law school so I can't do my own repairs anymore. wondering how many hours it'd take for a shop to do this.
also new brake boosters are crazy expensive would a used one from ebay be a bad idea?
also could this be the brake booster check valve?
to me it sounds like i can hear a air leak from under th dash from the pedal area.
I just moved to another city with my 944 to go to law school so I can't do my own repairs anymore. wondering how many hours it'd take for a shop to do this.
also new brake boosters are crazy expensive would a used one from ebay be a bad idea?
also could this be the brake booster check valve?
to me it sounds like i can hear a air leak from under th dash from the pedal area.
#2
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Probably the booster, but it might be the hose to the booster...
It's a pretty big job. Have to remove the master cylinder a it's hard to reach the booster from under the pedal cluster, if I recall. Then the system needs new fluid and bleeding when it's all together.
I wouldn't be surprised if a shop charged 6 hours of labor...
It's a pretty big job. Have to remove the master cylinder a it's hard to reach the booster from under the pedal cluster, if I recall. Then the system needs new fluid and bleeding when it's all together.
I wouldn't be surprised if a shop charged 6 hours of labor...
#3
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i wouldn't expect 6hrs for the change. i would check the hose before the booster. plug one end, blow air into the other, listen for whistling noise or feel for air.
if it's the booster, a used one migh not be the worst idea, but surely not the best, see i you can't fn a rebuilt unit, moe money, but usually a warrenty.
make sure your brake system isn't leaking. i looked at a 944 about 2 months ago, if you didn't look close, you woulda never realized that it was leaking, the pedal even felt ok
if it's the booster, a used one migh not be the worst idea, but surely not the best, see i you can't fn a rebuilt unit, moe money, but usually a warrenty.
make sure your brake system isn't leaking. i looked at a 944 about 2 months ago, if you didn't look close, you woulda never realized that it was leaking, the pedal even felt ok
#6
Drifting
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thanks for the info. where exactly are the hoses. would there be one under the dash or is it just the hoses you see attached to the booster in the engine bay.
when I step on the pedal I can hear air leaking out. my fluid level has not gone down at all.
i'm still driving it like this short distances to pickup groceries right now and back to my dorm.... it stops but you have to really stomp on the pedal.
also I believe my booster is the ATE model.
when I step on the pedal I can hear air leaking out. my fluid level has not gone down at all.
i'm still driving it like this short distances to pickup groceries right now and back to my dorm.... it stops but you have to really stomp on the pedal.
also I believe my booster is the ATE model.
#7
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Or just disable the boost. I kind of like the feel of unboosted brakes. Kind of weird in the paddock, but you will be surprised at how easy it is to adjust to on the track.
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#8
Drifting
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thanks for the info. where exactly are the hoses. would there be one under the dash or is it just the hoses you see attached to the booster in the engine bay.
when I step on the pedal I can hear air leaking out. my fluid level has not gone down at all.
i'm still driving it like this short distances to pickup groceries right now and back to my dorm.... it stops but you have to really stomp on the pedal.
also I believe my booster is the ATE model.
when I step on the pedal I can hear air leaking out. my fluid level has not gone down at all.
i'm still driving it like this short distances to pickup groceries right now and back to my dorm.... it stops but you have to really stomp on the pedal.
also I believe my booster is the ATE model.
#9
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I still dont get a grasp on having the booster. i'm a root 911 guy. 6 early ones now under my my belt. and a few 914s /Vws all no booster. - Sure my BMW's and my wifes SUV needs that So basically what's getting boosted pedal pressure - vacuum helping you push ?
#10
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I had a similar problem and it was the little "t" in the brake booster vacuum line. It had a crack. some creative super glue and duct tape solved this issue.....just throwing my .02 out there
#11
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the booster is amplifying the pressure from the pedal so you don't need to push as hard to jam on the brakes. i always found the stiffer the pedal/less assistance the more control of the brakes you get.
#12
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Just a thought. I have parted a few of these 944 cars and it seems there could be a potentiial for paint finish on the booster to lead to potential break in the o- ring seal at master cylinder o-ring. Some boosters show rust or paint wanting to come loose all the way up to where master wants to seal on the booster. That being said. Pull master clean up repaint that surface and add sealant and or a new O ring. It may get your vacuum back if all hoses and connections are good.
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hi.. i face similar problem.. the brake pedal goes back to original position slightly slower after braking (not very sure), and the braking effect lasted a little longer than usual after releasing the pedal. But I don't need to apply additional force to brake.. is this brake booster issue?
#15
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sounds almost like you have a collapsed brake line or lines, causing the fluid not to return to the master after braking- does it pull to one side when you touch the brakes? How about after you release them? Ive also seen some that were loosing fluid regularly that filled the booster up with fluid and that would make the pedal feel weird and maybe return slowly. Pumped out the fluid from the booster, replaced the master and was good after.