92 chevy caprice wagon engine vibration

Has 68000 mile on it and just recently start this vibration that shakes the car. I know it is related to the engine as whether I am idled or actively driving I feel the vibration. Now it does get worse at lower speeds with a lower rpm. If I floor it at low to dead stops it does not take off. Rather it is slow to accel. On the highway it is better with higher rpm. Though I can tell the vibration is still there. So what gives as I have had other caprices, but this is the first that has had a vibration like this. Also I have watched the engine block shaking while car is idling in the driveway. So I have a bad feeling, but I would like a clue before I take it in.

It could be many things. It may be nothing more than a spark plug or may mean serious engine repair. This should be easy to figure out by an qualified mechanic in a few minutes, at least most of the time. I would suggest you apparently don’t have a trusted mechanic, so either find one via a friend or family member or get two opinions.