Mysterious Engine Revving on my 97 GT - Help

[Capuano]

I've noticed a strange phenomenon lately with my 1997 Legacy GT. When approaching a stop light, I push the clutch pedal and start to hit the brakes. When I hit the brakes, the engine revs up to 3000-4000RPM's. As soon as I let up on the brake, it backs down to 1000. If I pump the brakes with the clutch in, the rpms will sometimes respond with the same high rev/low rev pattern. What is this? Is it a bad clutch, bad / clogged Master cylinder? What's the tie between the brakes and the clutch? Or is it just because I'm deccellerating, and the car is leaning forward? Any help is, as always, appreciated.
Mark

[SUBARU_TECH]

only at your own risk.in a empty parking lot.disconnect the brake booster hose and plug it.rember that your brakes will be manual and not stop easily.this is to check if the booster is leaking.also inpect the hose for leakage.in most cases i have found that the idle speed control solenoid is bad.diagnois as much as possible before replacing parts.

[Capuano]

Originally Posted by SUBARU_TECH

only at your own risk.in a empty parking lot.disconnect the brake booster hose and plug it.rember that your brakes will be manual and not stop easily.this is to check if the booster is leaking.also inpect the hose for leakage.in most cases i have found that the idle speed control solenoid is bad.diagnois as much as possible before replacing parts.

Thanks for the tip. I'll check it out and let you know how it went. As ususal, the dealership's mechanic just shrugged his sholders and said "I dunno". Now I've got a place to start. Thanks.

[SUBARU_TECH]

thats truly sad to here you got that reaction from your local dealer tech.sounds like it would be a easy diagnoisis if it happens that often.good luck and keep me up to date.would like to know the outcome.