my 1978 300d's brakes the pedal is firm but it still has weak stopping power ran the car pushed brake pedal and turned key off but car did not. that means a vacuum leak (right?). tested vac. line to booster, was 15. with the vac. line plugged i tried the same engine test and it passed does that mean my booster is bad?(internal leak?). also my brake light was on (not the wear light) it has fluid and parking brake was not On. upon closer inspection of this
the little thing under the rubber cover popped up when i pushed it back in the light turned off. what does that sensor/switch do?
thanks, time to go to work