The first thing you should do is find a new mechanic. Then ask the new mechanic to check system and control pressures for you. This should be about an hour's labor and is basic to a mixture problem.

Take a look at the vacuum line where it comes off the rear of the intake manifold by the firewall and follow it over to where it branches on the driver's side by the rear corner of the hood. IIRC, the line from the engine branches to:

- reserve tank under RF fender
- door locks (yellow)
- heat/ac (green)

Go buy some rubber fittings and a plastic "T". Try "T-ing" your vacuum gauge into the main line from the back of the intake manifold. Then unplug each of the lines above, and cap it on the vacuum side. See if the in-gear vacuum improves.

Also carefully inspect all the lines, fittings and rubber connectors for cracks loose connections.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe