Is there a resource/location that discusses common problems with the brake booster. I suspect a bad booster. they require a large amount of force to bring the car to a stop. The car has 275K miles and I have no idea if this is the original part. Is there a resource that discusses possible repairs? A new one is $250 +. I have checked the vacuum lines and all are attached with no obvious cracks or holes. I pumped the brakes about ten times and held the pedal as I started the engine. The pedal did not move when the engine started, so I suspect that there is no assist or "boost" being provided. Any suggestions or experience?