My M119 (500) suddenly developed a pronounced shaking, it was fine when I got to my destination. But started to shake when I started it up as I was about to leave.

Motor and tranny mounts have been replaced about 3000km ago.

Engine seems to be running fine and no misfire, shaking increases when put in "P" or "N", decreases when put in "D".

Any ideas?

Thanks.

 

Solved the problem, removed the air cleaner and looked around. There is a vacuum line connected right next to the injector for cylinder #1 (cylinder nearest front of car, left hand side when standing in front of the car) It somehow got pulled off, plugged it back in and shaking stopped.

 

I Agree the problem will be found in one of the vacuum hoses unfortunately mine where cracked from heat and time and I had to replace 12 various hoses

 

So engine shaking and Idle roughness are due to vacuum leaks? Mine is very rough at idle,sometimes going down to 500RPM and feeling like it is going to stall.I was thinking it was a timing or fuel injector issue maybe.After you replaced the vacuum lines did your Mercedes perform normally?

 

Engine shake can be caused by alot of things, and one of them is vacuum leaks.

I would start my trouble shooting with checking for vacuum leaks since it is one of the things you can easily do yourself. You just need a sharp eye to check out all the hoses and connections carefully, get a bright light source to make sure you dont miss anything. Look for loose, disconnected, kinked or damaged lines and connectors. Try disconnecting and reconnecting the hoses to make sure all are fitted snugly.

If you do find any problems, it should be quite easy and cheap to correct.

If you dont find anything, then your problem probably lies somewhere else.