Q: Could a leaking master cylinder cause the brakes to go to the floor very suddenly? 2004 Pontiac Grand Prix

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So I'm pretty sure my master cylinder is bad. I was pressing my brakes down when I was parked, and they felt normal, but then went to the floor very suddenly. I was able to drive a mile home, but I could barely get brakes when I pushed all the way to the floor. Could a leaking master cylinder cause the brakes to fail so suddenly?

My car has 200000 miles.
My car has an automatic transmission.

Hi - yes, a master cylinder problem, or a leak in the brake system anywhere, could cause "sudden loss of pedal". Check your brake fluid level first for low fluid. If fluid gets low enough that air gets in the system, the brake pedal will be VERY weak or spongy - air compresses, brake fluid does not. I would recommend a brake system inspection before driving any further by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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