Very glad to be a first time Mercedes owner. I bought a 1985 380se this past weekend and it is in very good condition, however there are two problems that I need fixed ASAP.First one is that it runs fast while in park or neutral ( about 1600 rpm) but as soon as I shift to reverse or drive, it drops to 600 rpm. After reading many posts here, I replaced the OVP and the idle slide valve. No change. Any suggestions? Also My central locking doesn't work. I know they are controlled by vacuum. They wiggle, but don't operate. Is this related?