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Brake pedal feel
Posted: Thu Jul 05, 2012 2:52 pm
by mitch_f1
So my pedal is usually a bit soft, which I can deal with; I drive around it. But if I use the brakes after accelerating hard and holding gear higher in the rev range (5k or so), then the pedal is maybe 50% or more stiffer. I've only recently noticed this, just wondering if it is normal.
Re: Brake pedal feel
Posted: Thu Jul 05, 2012 3:15 pm
by manga_blue
Servo vacuum non-return valve or diaphragm leak? Does it hold vacuum for long after you switch the engine off? Haven't heard of it in an MX5 before though. Sort of a British car specialty.
Re: Brake pedal feel
Posted: Thu Jul 05, 2012 3:19 pm
by mitch_f1
That's what I thought, but pumping the brake with the engine off produces a very very stiff pedal. I will maybe get 5 pumps before it is immovable.
Re: Brake pedal feel
Posted: Thu Jul 05, 2012 3:31 pm
by manga_blue
That's normal for pumping to use up the residual vacuum like that. If there's a leak then it would be losing vacuum pretty quickly with engine off and no pumping.
Re: Brake pedal feel
Posted: Thu Jul 05, 2012 3:51 pm
by mitch_f1
So you mean if I left it and went to push the pedal, it would be hard if there were a leak?