Here are the symptoms I've recently started seeing:
* Idle at 1500 rpm, usually will go down to 1000 rpm _after_ I come to a complete stop, but sometimes stays up at 1500 even then.
* Suspected vacuum leak but haven't been able to detect one. Replaced PCV with purolator supra valve and brand new hoses.
* Brake lights often fail to go off when the car is parked. I can get the lights to go off if I tap the brake pedal once or twice.
* Brakes occasionally feel mushy like there is air in the lines. Took it in to mechanic since I didn't have time and was told rear brakes needed to be adjusted (I had previously burned up the automatic tensioner cable in the passenger side rear brake due to the exhaust system putting pressure on the emergency brake). I do not know whether they did a bleed. They did not charge me.
* Windshield wiper motor seems to have failed. I would guess that this is unrelated but the motor is next to the booster, so maybe it is related?
If the problem were just the brakes I wouldn't suspect the booster, but since there appears to either be a vacuum leak or a problem with the AIS, I'm wondering whether the brake system is the cause of my leak. Can I verify just by closing off the vacuum line to the booster or is there a better way?
I was also hypothesizing that it could be a failed brake pedal sensor or that the pedal itself is sticking a bit, since according to http://minimopar.knizefamily.net/ecu/brake_sw.html the computer will raise the idle speed when the brakes are depressed (is this true for both manual and auto?).