Name: Sherman A. Johnson
Make: 2002 Impreza WRX
Mileage: Approx. 21,000 and 29,000
Time Out Of Use: N/A at this time
Problem and Likely Cause: ABS seems to be over-sensitive. It activates on smooth dry pavement and the brake pedal goes to the floor. Braking force is dramatically reduced. The cause is a mystery to me.
Modifications: Firestone SZ-50 tires (stock size). Hawk HP Plus pads with stock rotors. First instance was with Bridgestone RE 730's and stock brakes.
Submitted for Warranty Work: Yes.
Reason for Denial: No TSB from SOA. Problem hard to duplicate.
Your Story: I have driven cars with ABS since 1993. The first chance I got I began to test it's operation and limitations. I have activated it numerous times on wet/sandy/snow covered and icy roads. I am very familiar with how it should work. In my experience, the pedal stays firm, at about the usual distance off the floor but there is the vibrating sensation.
With the WRX, I have felt the typical vibration, but the pedal sinks almost all the way to the floor. In addition, in both instances I mentioned, I was on DRY pavement--no sand, leaves, etc. I hit the brakes hard in both instances, lifted, and then hit them hard again. The ABS activated both times upon the second application of the brakes. Normally it is next to impossible to activate the ABS (in my experience) with high performance tires on a smooth dry road. IF a driver were able to do so (and I have a couple times) the deceleration rate should stay about the same. At least that has been my experience with my previous vehicles, in particular a '93 NX 2000 with stock ABS brakes and Dunlop SP 8000 tires.
Bottom line: Based on fairly extensive experience (relative to the average driver) this layman's opinion is that there is something seriously wrong with the ABS on my WRX sedan. At this point I'm considering pulling the ABS fuse, at least until our first winter storm. I honestly believe the brakes would be safer with the ABS disabled.