Q: Brake pedal to floor when starting

asked by on March 12, 2018

I replaced the front disc brakes -- pads, rotors and calipers. When the engine is off I get normal resistance from the pedal. When I turn the engine on the pedal goes to the floor and no stopping power. I have not bled the brakes yet, should this solve the problem?

Also, one of the caliper slide pins keeps rotating when I tighten up the fastener so I can't torque it to spec. The other pin and fastener work normally. How do I fix this?

My car has 78000 miles.
My car has an automatic transmission.

If brake calipers are replaced, this will cause air to enter the brake system. The brakes must be bled in order to remove the air and regain pedal pressure. As for the slide pin, most of them have a spot to put an open end wrench to prevent the pin from spinning while you tighten the caliper bolt.

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