1984 300d Turbo
Found Vacuum Leak Very Slow, Fuel Door Lock Actuator Leaking Locking And Unlocking It Is Spring Load Open, Pull Panel Right Side
Remove Plug At Rear And Bend Top, 2=nuts Turn 1 Turn Ccw And Slide Up 2 Vacuum Connectors And Do Not Loose Spring On Shaft

Brakes, Trans, A/c Vacuum Controls Improvement Great Results Of
Trans Shifting If You Lock Doors Overnight And Push Or Pull The
Fuel Cover Open 8 Hrs Later Its Leaking, Check By Using Vac Tester