All Buick spark plugs are made to ignite the air/fuel mixture in the combustion chamber. This is their only purpose for which they execute repeatedly. The principal of this auto part has not changed since it was first developed over a century ago. What have changed are the metals the spark plug is made from and the configuration of the electrode and the end of the plug. For each cylinder on your Buick, there is one spark plug. The electrical current supplied to the plugs is generated from the ignition coil that is connected to the distributor of your engine. During most tune-ups, when your Buick spark plugs are being replaced, the wires, distributor cap and rotor in the cap should also be inspected. On average the cap should be replaced every 2 to 3 tune-ups with the wires about every 4 to 5 tune-ups. This will provide the correct amount of voltage to set fire to the fuel being used by your automobile. The timing of the electricity sent to your spark plug is regulated by the contact between the rotor and the distributor cap. This connection can become fouled just like the spark plug and should be cleaned or changed with each tune-up. Many of the newer Buicks on the road no longer have a distributor and the electrical voltage is generated by the onboard computer. Know just what is on your Buick so you will be informed and know if your technician is having you to purchase parts your car does or does not have on it. The most often forgotten spark plug when replacement is done is the rear passenger side of the V6. This can only be accessed thru the fender well of your car. When looking at the old spark plugs taken off your Buick, if there are two different kinds or ages of plugs, then one of the plugs was not replaced previously.