Car dictionary: automotive terms

Volkswagen 2.0 TSI engine alternator

An alternator supplies an electric power for the vehicle's electric systems and charges the battery when the engine is running. An alternator is rotated by a drive belt connected to the engine crankshaft.
If the alternator fails, the warning light or "CHARGE" icon comes on on the instrument panel.
Alternator problems are common. If the alternator fails it needs to be rebuilt or replaced.

Ball joint

A ball joint is a part of a vehicle front suspension. Most cars have one or two ball joints at each front wheel. A ball joint is lubricated inside and sealed with a rubber boot. When a ball joint becomes bad, a vehicle could be unsafe to drive; a ball joint, when badly worn, can separate causing the vehicle to lose control unexpectedly.
One of the possible indication of a bad ball joint could be a knocking noise coming from the front end, particularly while driving over bumps or making sharp turns. If you suspect your vehicle has a bad ball joint or any other suspension component, have your car inspected as soon as you can, it can be unsafe to drive. It's recommended to check the vehicle's chassis in a garage on a lift at least once a year to discover potential problems with suspension, brakes and other components.

Typically, the engine bank that contains cylinder 1 is called Bank 1

The engine Bank is the group of cylinders aligned together. The term Bank 1 usually refers to the bank of the engine that contains the cylinder number 1.
In an in-line 4-cylinder engine all 4 cylinders are grouped together, so there is only one bank (Bank 1).
A V6 or V8 engine has two banks (see the diagram), each with three or four cylinders respectively. Usually, in a V6 or V8 engine, the bank that contains the cylinder 1 is called Bank 1 and the opposite bank is called Bank 2.

The battery provides electric power to start the car. I get many questions like "My car doesn't start, it only makes a click-click noise when I'm trying to start it" - this is most likely the result of the battery having decided to quit. Unfortunately, usually it happens unexpectedly - the battery just stops working one day. If your vehicle doesn't start and you suspect the battery, there is a simple way to check it. Try switching the wipers on - if they move very slowly, a lot slower than usual (too low voltage) the battery is probably discharged or dead.

Control arm

Lower control arm. Ford F150

A control arm is a part of the front suspension. Some cars have one control control arm on each side; other vehicles, including many trucks have two (upper and lower) control arms on each side of the front suspension. The internal side of the control arm is connected to a vehicle's body or a frame through the rubber bushings (control arm bushings). An outer end of the control arm holds a ball joint. A ball joint could be bolted to or pressed into the control arm. Sometimes, a ball joint is an integral part of the control arm and if it goes bad the whole control arm must be replaced.
One of the common problems with control arms is when the control arm bushings wear out. Sometimes the bushing can be replaced separately. Typically they have to be pressed into the control arm.
In some cars if the control arm bushings go bad, the whole control arm has to be replaced as it comes as an assembly.
After the control arm bushings or the whole control arm is replaced, the wheel alignment must be performed on most cars.

CV joint.

All front-wheel drive cars as well as some four-wheel drive vehicles have Constant Velocity joints or CV joints on both ends of the front drive shafts; the inner CV joints connect the drive shafts to the transmission and the outer CV joints connect the drive wheels to the drive shafts. The CV joints are needed to transfer the torque at a constant speed to the steered wheels as well as to accommodate up and down motion of the suspension. A CV joint is packed with a grease and sealed tight by a rubber or plastic boot. A CV joint doesn't need any maintenance and can last very long, as long as the protective CV joint boot is not damaged. Read full article: CV joint

Ford EGR vacuum-operated valve

The EGR system (Exhaust Gas Recirculation system) is designed to reduce emissions. To be precise, it lowers the amount of nitrogen oxides (NOx) in the exhaust gases.
Nitrogen oxides are formed at very high combustion temperatures. The EGR system re-routes a part of the exhaust gases back into the intake manifold, diluting the air/fuel mixture. As the exhaust gases are not combustible, mixing them with the air/fuel charge helps reduce the combustion temperature.

Ground connection

Whenever a car has some electrical problems, you often hear about a ground connection or 'ground'. Modern cars have a 12-volt electrical system where the positive battery terminal (+12V or 'power') is distributed through wiring and fuses, while the battery negative "-" terminal is connected to the car's body ('ground'); thus a car body acts as a conductor. Most of the electrical consumers in a car receive their positive voltage (+12V) through the fuses and wiring, while the negative side is usually connected to a car body, like the ground terminals in the photo. A bad connection at one of the ground terminals can cause various weird or hard to trace electrical problems. For that reason, with any electrical issues, 'power' (+12V) and 'ground' are usually checked first. Sometimes a ground terminal can get loose or corroded causing poor connection.