I also am having vacuum leak problems. I fixed one last evening and I think there may be another source. With a hand vacuum pump with gage 'Teed' into the main vacuum source in the power brake booster area, I get a vacuum reading of 5 inches with the engine idling. (The fuel shutoff works at a minimum of 4 inches, so this is barely enough). With the engine running at 5 inches vacuum, when I pinch the rubber connector going to the brown line, the vacuum rises to at least 10 inches. Pinching the other colored lines (green-CLIMATE C; yellow-LOCKS; yellow/black-RESERVOIR)does not change the vacuum value.

My question is, should the brown line be contributing to that much of a vacuum loss, or is this a sign that the ignition vacuum switch has gone bad?


Gary

'79 300D