My 1994 E320 wagon with vacuum actuated door locks has a problem. The key got stuck in the driver's side door lock cylinder and when the key was finally pulled out the cylinder came with it. I took it to a locksmith who advised me to take out a few defective "teeth" that did not retract completely with the key in the cylinder. I did that, and replaced the cylinder. The key now turns but without unlocking the door. The lock on the passenger side locks and unlocks all the doors just like always. The set screw on the driver's side appears to only hold the door handle in place (the part where the cylinder is) - it does not hold the lock cylinder in place. When I turn the key in the cylinder it does not feel as if there is any resistance to movement like there used to be, as if a "linkage" is missing. The key does go in and out nicely, though.

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Chip Johnson