Quote:
Originally Posted by martin93
Well mine has never had a firm notchy pedal. And hate to sound like a knowitall Bob, but rear disk brakes should not need a hard stamp in order to adjust up the handbrake. This should only apply to cars with rear drums which have an auto adjuster in them. Rear disk brakes adjust naturally when the pedal is released, which is why as the brake pads wear, the fluid level gradually drops as the growing space between the caliper piston and bore is taken up with fluid.
I would third on it being a brake servo issue rather than a caliper problem. Although I would check the caliper sliders aren't seized just to make sure, as to me greasing these up are a yearly service item.
Biggest issue I've found with servo's on older cars is the brake master cylinder leaking fluid into the actual servo causing all sorts of problems. I would check the one way valve first as pierremcalpine suggested, and make sure there are no leaks on the hose and its connections. Then have a look for any signs of fluid on the vacuum pipe going into the servo while you're there.
So to conclude, I would say it's a brake servo or master cylinder problem.
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Depends how you drive your car. I use a lot of engine braking and rarely use hard or firm braking to slow down. I've never had to adjust the handbrake travel on my car which had handbrake failures on most its MOTs before I bought it.
The piston in the calliper is held by the rubber seal and does not move in and out in relation to the seal but just flexes the rubber seal when you brake. So as the pads wear the handbrake becomes slacker and brake travel longer until a firm or harsh application of the pedal shocks the piston free from the grip of the seal.
If I deliberately do this the handbrake and brake pedal travel decreases.
The notch people feel is perhaps the EBD kicking in as the rear wheels start to slow down faster than the fronts and the ABS pump opens up a valve to allow more brake pressure to the fronts. This is apparently how the ABS systems of this era were set up.
As a side note, I believe EBD was only fitted to phase II cars from 2000-2004.