Name: B Reed
Make: 2002 Impreza WRX Sedan
Mileage: from ~20000 til 34500 (current)
Time Out Of Use: none
Problem And Likely Cause: Sinking brake pedal / fluttering brake pedal
Submitted For Warranty Work (Yes/No): Yes
Reason Given For Denial: 1st, brakes operating as designed, 2nd, brakes still working as designed, cause = brake booster loosing pressure under deceleration
My problem sounds almost identical to sajohnson's prob. Under normal braking conditions (not hard braking) the pedal falls about .5 to 1.0 inches towards the floor. Brake pressure seems fairly constant. Under hard braking its solid until the car slows significantly. This started at about 20,000 miles right after I had a flat and used the spare donut to get to a tire place to patch the tire.
I took it to Big Valley Dodge/Subaru in Van Nuys. Had them check it during an oil change and they said it was working fine. Went back a second time 2000 miles later and went for a drive with a service technician. They charged me about $50 for a full brake inspection and said it was fine.
Recently, I took the car to an independent service place (Suby Specialties in Monrovia). Without even saying a word about the brakes they took it for a road test and said something was very wrong with the brakes.
Today I took it to Mazda/Subaru of Thousand Oaks. Within about 20 minutes they reported that the ABS module was probably bad. They mentioned there was a bulletin on this problem for owners who drove more than 3 miles on the spare tire. Apparently, it has the ability to "burn the ABS module". This doesn't make a lot of sense to me, but they are ordering a new ABS module for replacement under warranty.
Can anyone explain this to me? Thanks!