An acronym for Data Link Connector. Formerly referred to as the ALDL, this is the connector to which diagnostic scan tools are connected. Under OBD II, the DLC is a standardized 16-cavity connector and has a standardized location under the

The process of going from a higher gear (for instance, fourth gear) to a lower gear (for instance, second gear) with a manual or automatic transmission.

Also called a fan belt or serpentine belt, drive belts are used to drive the engine’s accessories, such as the alternator, power steering pump, or air conditioning compressor. A serpentine belt is a wide single drive belt that drives all

The system of components that connects the transmission to the wheels. The driveline consists of axles, differentials, constant velocity (CV) or universal joints, and, for cars with rear-, four-, and all-wheel drive, a driveshaft.

In rear-, four-, and all-wheel drive cars, the driveshaft is the tube(s) that connects the transmission with the differential(s).

Cylinders are the large round holes in the engine block that contain the pistons. The pistons travel up and down in the cylinders to create the engine’s power.

The cylinder head is the top part of the engine. It often contains the valves, and for cars with overhead cams, it contains the camshafts as well. The cylinder head also forms the top part of the combustion chamber.

The process by which the air/fuel mixture burns within an engine to create power.

The area in the cylinder head where air/fuel is ignited to create power.

Comprehensive coverage includes protection against theft and accident damage, regardless of fault.

A special gauge used by technicians to measure how much pressure a cylinder can create.

A test to see how much pressure a cylinder can create.

Also called antifreeze. The fluid mixed with water that is put into your vehicle’s radiator. Antifreeze is traditionally green in color; however, newer long-life antifreezes may be red or orange. Please refer to your vehicle’s owner’s manual for the proper

Many cars have a clear plastic reservoir that allows the owner to see the level of their vehicle’s coolant. Check your owner’s manual to find the coolant reservoir on your vehicle.

The system of components that keeps your engine at the correct operating temperature. The cooling system includes the radiator, radiator cap, coolant reservoir, cooling fan, water pump, thermostat, hoses, heater core, heater valve, and antifreeze.

The cooling system hoses allow coolant to circulate between the radiator, engine, and heater. Over time, they deteriorate, and should be checked annually for condition and possible damage.

Cracked paint occurs when a paint is so damaged, the surface actually develops cracks. These cracks may spread in a spiderweb fashion across the surface of the paint. Cracked paint is unrestorable, and must often be completely removed when a

The crankshaft is an engine part that takes the up and down motion of the pistons and translates it into circular motion that can be directly transferred to the drivetrain.

Crazed paint occurs when paint is so damaged, the surface actually develops hairline cracks. These cracks may spread in a spiderweb fashion across the surface of the paint. Crazed paint is unrestorable, and sometimes has to be completely removed when

Cruising is a driving style whereby the driver maintains a set speed with very little fluctuation.