Today, when I parked my car, I noticed that the RPM needle kept moving up and down ranging from 500-800ish and felt the car shake. I popped my hood and can see my engine shake/rattle everytime. What may be the problem?

 

When was the last time you did a tune up. Plugs, wires, etc...

 

i personally never did it, but i have a log of when i changed my oil and spark plugs and other maintenances.

 

Probably time then, to change the distibutor cap, rotor, plugs, and wires.