This happens when the brake booster push rod is adjusted out too far which does no allow the brake master to return fully holding the brakes on . To confirm the issue loosen the brake master mounting bolts 3 turns to see if the car starts to roll again, if so remove the master and adjust the booster push rod inward. Also a brake flex hose can come apart internally causing a short of check valve in the system but this is usually isolated to one brake either front or rear Parking brake cable stuck partially-applied. Restricted rubber flex hose. Brake fluid contaminated with a petroleum product.
Park on a slight incline, shift to neutral, and verify the vehicle won't creep downhill on its own. Crack open the steel lines at the master cylinder. If the brake releases, suspect contaminated fluid. If it doesn't release, open the bleeder screw on the caliper. If it still doesn't release, suspect the parking brake cable.
Dec 2, 2012 at 3:48 AM
