DJB

The brake pedal on my MY98 has developed an annoying feature. The pedal feel changes depending on my style of driving. Braking hard a couple of times raises the firmness level of the pedal whereas driving for a few miles without using the brakes, the pedal becomes spongy and pedal travel is further. The means that smooth driving can be difficult since I don't know how hard to press the brake each time. Stopping ability is unaffected.

I changed to EBC Greenstuff front pads and EBC discs (non-turbo groove) about 2 months ago. The problem was present before this. Here's my list of possible explanations.

1. Air in the brake line? Unlikely, this would surely make the pedal spongy all the time.

2. Bulkhead flex (as is rectified by brake master cylinder support bracket) - This would be more likely to affect heavy braking. I've found the opposite.

3. Rubber brake hoses? Same as No. 2.

4. Rear brakes faulty - no reason to suspect this.

5. I reused the anti-squeal shims when I changed the pads (they were rusty) - could these create a variable gap between the piston and the pad which enlarges when the brakes are not being used?

I think the last suggestion is the most plausible. What do you think?

D.

Hoppy

According the the handbook in my UK00, this is normal. Check your manual and run through the pedal routine with engine on/off etc.

Richard.

Gareth Allan

So its not just me then!

My 99UK does exactly the same, but not all the time - usually only when critical! For instance, at the end of the straight at knockhill..

I get the same effects, in that the pedal seems to go almost to the floor, but if you give it a quick pump and release, then go again, its like the pedal is instantly solid under your foot. There does not seem to be any difference in stopping distance, as you just need to stand on the pedal to the floor to stop, but it certainly gets the heart going.

Perhaps it is due to heat, as i have recently upgraded the fronts to godspeed 335mm set up and have not been able to reproduce the same thing since, but have not tried 10 laps at knockhill yet either. (but it used to happen after less laps than that)

I have not had a chance to check the book yet, but cant see how anything done 3 hours before when engine is off will effect the brakes after 3 hours 150 miles.

Gareth

DJB

Hoppy

I've had a look at the handbook - not sure what you mean. There's a short section about checking pedal free play. The problem only really occurs out on the road especially on A roads and M ways where braking is infrequent.

D.

Hoppy

DJB, handbook says:

1) With the engine off, depress the brake pedal several times, applying the same pedal force each time. The distance the pedal travels should not vary.
2) With the brake pedal depressed, start the engine. The pedal should move slightly down to the floor.
3) With the brake pedal depressed, stop the engine and keep the pedal pressed for 30 seconds. The pedal height should not change.
4) Start the engine again and run for about one minute then turn it off. Depress the brake pedal several times to check the brake booster. Brake booster operates properly if the pedal stroke decreases with each depression.

On my UK00 car, the pedal acts exactly as above. Also, while on the move, a quick dab of the pedal firms it up considerably, as you describe, but does not actually improve braking. By the way, I have big APR brakes and can trigger the ABS from over 100mph so they seem to be working okay

I would just add that Subaru improved the brakes with MY99/00 cars, so yours may be different.

Richard.

DJB

I removed the anti-squeal shims today and there has been a significant improvement in pedal feel at all times. I have to test the car over the next few days to see if it lasts.

D.