These are fitted on the above and below side of the engine and may in most cases be hidden from view particularly when the car has the additional features like air conditioning or power steering which may require an extension or swivel spark plug. A spark plug wrench or even spark plug socket that screws on a ratchet wrench should be used to remove or fit spark plugs, but the wrench should be insulated to protect the porcelain insulator of the spark plug, a feeler gauge must be used to measure and set the spark plug gap. If the vehicle has HEI ignition between 1975 and 1980, this spark plug wire removal tool is advised for disconnecting the wire boot from the spark plug. Although most of the spark plugs can look similar, it is recommended to buy new spark plugs in advance, set the optimum spark plug gap and install spark plugs one-by-one while choosing the right spark plug type for the specific engine, preferably according to the tune-up decal data. Before the removal, ensure that the engine has cooled and also examine the new spark plugs for any kind of defects and also to check the gap using a thickness gauge to ensure that it is as per the specifications required. Tie the fenders to avoid scratching the paint, the spark plug wire should be pulled by holding the boot, it might require twisting to release, and used compressed air to clean the spark plug. Take out the spark plug working anticlockwise with the help of the wrench or socket and then check it to a reference so as to know the condition of the engine while running. Put a new plug and tighten it delicately and if it does not turn easily offer it every other angle so that it does not interlock with the other thread. Torque the plug with a wrench/socket, although a torque wrench should be used for proper seating, then before connecting it, ensure the plug wire is arranged appropriately its located away from the exhaust manifold. Do the same for other spark plugs by swapping them until all of them have been replaced, but never at the same time to get confused with the wire connectors.
