leaking air behind brake pedal, is there a simple fix
car dies periodically and sometimes doesn't want to start. This air hissing
started shortly after symptoms.
Air leaking behind the brake pedal more than likely would be the brake power booster that is leaking. You should start to notice that it would be getting harder to press on the brake. The power booster would need replacing. But also look underneath by the brake pedal to make sure there are no vacuum lines running by that may have a leak in them. Check this first.
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