Hello everyone. I just bought my first M-B yesterday, so I'm brand new. I have a beautiful 1984 300cd with 170k. Although I love the car, it does have pretty hard 1-2 shifts and it doesn't seem to have any power. I have done some reading and today I did some investigation. I would really appreciate some input here from the more experienced members. I'm primarily trying to improve the really harsh shifting. Here's what I did/ found:

1. I checked the vacuum lines with a mityvac. Everything seems to hold vacuum well except for one line that slowly drains vaccum. Strangely, (or maybe not) the vacuum drain makes a weird moaning noise from some small component on the front passenger fender - not sure what this is yet. Also, someone had plugged one of the black lines coming off of this component - I reconnected it.

2. I cleaned the banjo bolt. The line from the banjo bolt to the switchover unit had been removed and plugged up with a screw for some reason. The banjo bolt was completely occluded with gunk, so I cleaned it up and will reattach it tomorrow. Unfortunately, the pressure line was brittle and snapped in two, so I will have to find some kind of replacement line tomorrow. Any suggestions?

3. Also, when I am in the car, the door locks cannot be moved by hand on either door- is this normal? The key works to lock both doors from the outside, but the door locks on the inside feel like they are stuck. Does this have anything to do with the vacuum system too or is this an unrelated issue?

Any other suggestions on how to improve the shifting? I was thinking that maybe the car is not getting enough power due to the ALDA system not being functional. My hope is that when I get the lines hooked back up tomorrow, more power will be the result and the shifting may improve. Anything else I can try?