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Old 05-10-2008, 04:34 PM   #2 (permalink)
shingleback
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Date registered: Apr 2006
Vehicle: '87 190D 2.5 Turbo, '03 3.2TL-S 'A-Spec'
Location: Vancouver, Canada
Posts: 558
That sounds quite normal; when the engine is off and you press the brakes, you are using up the vacuum reserve in the booster. After a few times you have run out of vacuum and the pedal is very hard to press. That is why the pedal action gets progressively harder.
When you start the car with the pedal pushed down, the vacuum builds up and assists your leg in applying the brakes, so you can 'feel' it go down a little; in fact, it is probably the feeling of the assist taking the effort away from you.
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