Will this work if my car's lighter socket is broken or weak?

Test the socket with another 12V accessory first—phone charger, dash cam, anything that draws power. If it works, the compressor will too. If the socket is dead, you'll need it repaired at a shop or use a battery terminal clamp adapter instead.

How long does it take to inflate a tire from flat to pressure?

Inflation time depends on tire size and how low you started. On a standard car tire, expect several minutes. Keep the engine running to maintain consistent 12V power output.

Can I use this while driving or only when parked?

Park and turn on the engine. Don't try to inflate while moving—you need both hands free and a stable platform. The cable length is designed for stationary use at your vehicle.