2001 Escape Brake Pedal "Hiss"

"John Keiser" wrote

Description and a Flash movie of the booster in action:

- The seal between the housing and the piston assembly has gone bad.

- The internal valve isn't seating properly, allowing outside air to constantly leak through the booster. Could be a piece of dirt, a chunk of the air filter (the pedal's pushrod goes through a foamy, spongy thing... the filter), or some kind of corrosion on the valve's seat keeping it from closing. Pressing the pedal a bit moves the internal valve enough to seal the front chamber from the rear, so no more flow.

When mine started hissing years ago, by the time I got it to the shop later that day (maybe a 20 minute drive), I had to stand on the pedal with both feet to stop, so yes, it IS a critical safety issue, unless you don't care about your life or that of others around you.

Replace it.

You problem can progress to a sudden catastrophic failure very quickly without further notice. It is a safety concern and should be repaired at the earliest opportunity with as little vehicle operation as possible until it is repaired. The ass you save may be mine!

Lugnut

I made an appointment to have it fixed [under warranty].

Thank you for the feedback.

Good move! Glad to hear you have someone to contribute to the cause.

Lugnut

Is it me or is there some kinda of booster failure lately? Its been so long I can't remember the last time I saw a bad booster.

I've owned cars for 40 years [generally much older models than this] and never had a problem before.