S60 - Could a misfire cause constant shaking?
 

Got a good deal on a 2001 S60 non-turbo with vibration issues. 125K on it. Only driven about 10 miles since the shaking began, so I don't think any serious damage has been done.

Anway, the car shakes very noticeably upon start up, idle, and throughout acceleration. Gets better at high RPM, but still noticeable. Gonna rule out alignment and CV joints because of the idle. I know the list of possible causes is extensive, though before taking it to a dealer I'm going to try my hand at it at my shop - agricultural mechanic ;)

The CEL is on - checking codes tomorrow. I'm thinking motor mounts, leak somewhere, or coils/plugs. Am I on the right track? I am leaning towards coil failure. I wouldn't think that the CEL would come on for bad mounts or a leak. But what do I know? Maybe it does.

The severity of the vibrations is what concerns me. I would think that the misfire would have to be on multiple cylinders to cause the kind of shaking present.

Any suggestions? :)

If it shakes with the car not moving, it's likely a misfire. The fault codes will help.

Sounds like a dead miss. A dead miss on one cylinder creates lots of ugly vibration.

Just an update for any future viewers with this issue.

Problem was a dead coil on cylinder 3. Replaced it with a genuine volvo coil and replaced all spark plugs for good measure. Car runs like a champ!

Thanks for the help!