my brake pedal is stiff when my car is not running . when i start it the pedal, when pushed goes right to the floor
Either the master cylinder is bad or you have a leak in the break system.
Master cylinder, if you had a leak the pedal would drop even with the car being off.
someone with a similar problem traced it to the vacumn booster for the brakes.
The car would have to be running. Then if the brake booster is bad the brakes will get stiff.
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