Question about 2008 Toyota RAV4

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Brake pedal goes to floor when first applied. Fluid within limits. No signs of leak(s). Hissing sound noted. No vibration.

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Pump the brake pedal 5 or 6 time and see if it comes off the floor, If it does hold the pedal there for a few minutes and see if it drifts back to the floor. If it drifts slowly back to the floor. And there are no leaks as you said most likely cause is the master cylinder. If it stays up after holding for a few minutes most likely air in the system. Do this quick test and get back with me.

Posted on May 29, 2011

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Hissing sound indicates booster diaphragm has torn. Please let me know if you would like instructions for replacing the booster.

Posted on May 28, 2011

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