While your car is idling there is a large amount of vibration that can be felt.
Car Problem Diagnosis
A car engine vibrates excessively while idle it indicates problem that is related to engine firing. Car engine cylinders needs to fire in a correct order so that the car engine will run smoothly. If one or more of the cylinder improperly fires or misfire then this cause imbalance on to car engine which will transmit to the whole car and as a result an excessive vibration is felt even when the car is idle.
Engine misfiring can cause by four reasons namely a bad spark plug, bad spark plug wires, a worn distributor cap, or a one of the valves is burned. All of the three reasons except for the worn valve can affect the firing of the air/fuel ratio into the car engines cylinder, as for the burned valves, this can cause improper compression which can result to engine misfiring.
Possible Cause of Too Much Engine Vibration
How to Fix Engine Vibration at Idle
Since most of the cause of this kind of problem is a faulty spark plug and spark plug wires, to fix the problem begin on the replacement of the said two parts, if the new spark plugs and spark plug wires cannot correct the problem then proceed with the replacement of the distributor cap. Any auto parts stores sells spark plug, spark plug wires, and distributor cap you only need to shop around for the best price or you can buy online at Amazon replacement parts store so that you can be sure that you get the best quality at an affordable price. When replacing the parts yourself consult a repair manual, or if you want hire a mechanic to do the work for you after all it is cheaper than bringing the car to a repair shop.
However, if replacing the distributor cap does not fix the problem then this means that the car has burned valves, now this is the time to bring your car to a reputable auto repair shop for confirmation.