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Discussion Starter #1
Can anyone point me in the right direction to find the brake booster? brakes are firm/hard to press the pedal. still functional, no impact to steering currently. suspect tear in booster diaphragm, but would like to know where she be.

thx i a
 

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Like most cars, the booster (called a "servo" unit in the UK, as in servo-assisted) is directly behind the brake pedal (there should be a push rod at the top of the pedal that goes in to the servo) and the servo/booster is attached directly to the master cylinder, which is usually placed close to/underneath the brake fluid reservoir, connected by a short hose or directly attached as in the case of the 124 Spider. So if you work backwards from the pedal or downwards from the reservoir, you should find it. The other way is to trace the vacuum line back from the inlet manifold usually via a non-return valve to the servo/booster. The attached diagrams are from ePer with part number that don't apply in the US, but the equivalent parts can be found easily.

Screenshot_20200106-203906_Firefox.jpg Screenshot_20200106-204648_Firefox.jpg
 

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Can anyone point me in the right direction to find the brake booster? brakes are firm/hard to press the pedal. still functional, no impact to steering currently. suspect tear in booster diaphragm, but would like to know where she be.

thx i a
It's always in front of the driver seat in the engine compartement. So in the picture I uploaded, look at top right, you see Brake oil container, behind on the firewall you see a a big dark round drum, well that's your brake booster or power brake.
 

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Check the large hose that goes into the brake booster. It could be detached or have a breach in it. Once you have vacuum (i.e. take your foot off the accelerator and the throttle plate closes), it should preload your brakes. So they should be easier to press, not harder.
 

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Discussion Starter #5
thanks much all. i will give that a try and post my findings
 

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Discussion Starter #6
all looks well, but i traced the line and the same vacuum line is where the forge blowoff plate hooks into. suspect i have a leak somewhere at a fitting
 

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Discussion Starter #7
Found the problem. My son didn't connect this vacuum line under the v4 intake when disassembling and reassembling to improve routing for lines for forge blowoff.
 

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Discussion Starter #8
That caused intermittent loss of vacuum, and turbo performance was also compromised significantly
 

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