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Symptoms of a bad brake booster.

  • Thread starter Thread starter Mustang5L5
  • Start date Start date Nov 21, 2009

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,264
17,952
224
Massachusetts
Nov 21, 2009
#1
  • Nov 21, 2009
  • #1
Would you guys replace the booster in this situation.


Cobra brakes (99+ front calipers). Running an 95 V6 used Booster with a brand new 93 cobra MC.

I don't drive often, so i can't remember if it's been slowly degrading over time. Basically, i hear a light hiss when i press the pedal and sometimes if i jump on the brakes fast while pushing in the clutch, it stalls the car out.

Also, i notice at higher RPM's, the brakes are a little harder than at low RPM's. Car still stops nicely, but the pedal is a little inconsistent.

With the engine off, the pedal pumps up hard as a rock. With my foot on the brake, i start the car and the pedal sinks a bit as it gets vacuum.

I also notice playing with the 1-way valve on the booster does affect how it feels. It's almost like it leaks slightly. Can i pick this part up separate somewhere?

So what would you guys do? Should I just order up a new 93 cobra booster over the winter? Brakes are important to me, and i should have just installed a brand new booster from the beginning.
 
9

94gtfreak

Active Member
Oct 19, 2008
412
4
39
your moms house
Nov 21, 2009
#2
  • Nov 21, 2009
  • #2
Personally I would just get the Cobra booster. Brakes are not an area to slack around in.

I'm not 100% positive but I think you can get a new one way valve, but idk?

Maybe someone with a lil more intelligence will speak up and help out a lil more?
 

87GT Drop Top

Member
May 1, 2009
500
3
17
South Florida
Nov 21, 2009
#3
  • Nov 21, 2009
  • #3
The hissing sound is the booster going bad. The diaphram has a hole in it. It's going to go out completely without warning. You are going to use the brakes and them BAM no power assist. Hopefully you don't hit anything. I would replace it ASAP.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,264
17,952
224
Massachusetts
Nov 21, 2009
#4
  • Nov 21, 2009
  • #4
Guess i'll order one over the winter. Car's going to sleep til next spring
 
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