Hi Andrew

It does sound like you have a warped rear disc. Your dealer should be able to replace this under warranty and you will not need to put your old front brakes back on.

The spongy pedal bit is when you have brake fade. This means you have found the limit of your brake's ability.

 

Thanks Pete, you have reassured me about both issues.

Andrew...

 

I have, what I believe to be, a brake disk related problem, however, the symptoms do not seem to fit any of the descriptions I have read of warped brake disks, this may be because IMHO it is the rears that have warped/worn unevenly.

Firstly the car:

MY98 Turbo Wagon with 28K miles, front brakes swapped to Subaru 4 pots off a 9K miles P1 about 1K ago, braided hoses and uprated fluid, currently std pads (was going to get new until this problem appeared.) std rear brakes.

There is plenty of material (>5mm) on both front and rear pads.

The symptoms were there in a milder form before I swapped the front brakes, and the guy I bought the brakes off swears there was no problem on his P1 (he is well known contributor on this BBS).

Firstly the symptoms:

1. At low speed (<20 mph) hot or cold - slightly uneven braking, when coming to a halt.

2. At medium speed (<40mph) when cold - slight unevenness but virtually undetectable.

3. At medium speed when hot - pulsing through the brake pedal, slight vibrations, nothing felt in the steering wheel.

4. At high speed when hot, light braking, vibration in the brake pedal, vibration in the car, slight vibration in the steering wheel (difficult to sense), vibration is worse in rear of car.

5. At high speed when hot, heavy braking, initial braking is good but then effectiveness seems to decrease, brake pedal softens.

Now the questions:

1. How do I identify exactly where the problem lies?

2. If it is a rear disk problem, are they covered under warranty? and will I have to put my 2 pots back on before taking putting the car into my dealer?

Andrew...

 

The spongy pedal may also be due to air in the system. ABS equipped cars are notorious for being difficult to bleed due to the complicated pipework in the distribution block under the bonnet.

 

Andrew

What wheels have you fitted? did you have any trouble with the 4-pots fouling? I got a set of Subaru 4-pots for my 98 Terzo, but found to my disgust that the 17" speedlines wouldn't clear the outside of the calipers (wrong offset?)

 

madmike,

I've go the standard 98/99 16" Wheels which clear the calipers fine.

AndrewC.