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Hello,

I just got my car out of the garage as its been stored most of winter and been driving it.  I then noticed my brake pedal was hard to press and pretty wooden/stodgy.

 

The car still stops but it wont lock up or kick in ABS.  There is no ABS light.

 

I think its the booster but I looked for a vacuum leak but could locate one.  If its the check vavle in the booster where is this and how can I fault find.

 

Any help be great.

 

Thanks

 

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https://www.sau.com.au/forums/topic/472866-r32-gtr-brake-booster-issues/
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Check valve is easy.  Remove hose from both end connections.  Suck and blow at one end.  If you can both suck and blow, it's broken.  Get a new one.

The booster can also suffer a broken diaphragm and can leak at the shaft seal.  It's surprising that this is the first time you've had this on this car.  I did the booster in my R32 at the beginning of the century.  You can get them rebuilt.

All checked and ok.  

Talking to some brake companies and they reckon a couple of things.

1) Wheel and tire combo is decreasing brake performance.

2) might have been a small bit of film or something on the rotor that didn't help at the time as it feels slightly better.

 

They seem to think that big wide wheels will decrease braking performance -  see it all the time apparently.

 

 

 

yeah. Pull off the vacuum line that goes to be booster and block it off on the engine side, and see if the braking changes at all.

dead feeling pedals can have lots of causes including glazed pads or rotors. Cold race pads. Not generally water or air in the brake lines because gives you a "holy shit the pedal just went to the floor and I'm going to drill that camry" in traffic kind of feeling

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