How do I find out if my master door switch is bad or good? I removed the black cover on the front passenger side floor and i can pull a good amount of vacuum on all the red lines except the one going back to the trunk and gas door. I removed the trunk vac element along with the gas and blocked them and still cant pull vac on those lines. What NEXT ????? By the way having trouble with shutting car off and locks not working. 1980 300D

1984 300d Turbo 140k
Pull The Right Rear Trunk Panel And Check Vacuum For The Gas Cover Actuator If Leaks Replace, Some Leak Over Night Lock Doors And Open Cover, You Have Found The Leak,