Automotive terms Modern (C)
Automotive Technical terms and abbreviations overview used in the industry, Guide and explanations.
The following are examples of Mid Modern technical terms C recommended for general use worldwide. For in-depth specific terms also see terms for historic vintage and specific areas such as Paint.
A hydraulically activated device in a disc brake system, which is mounted straddling the brake rotor (disc). The caliper contains at
least one piston and two brake pads. Hydraulic pressure on the piston(s) forces the pads against the rotor
The quantity of electricity that can be delivered from a unit, as from a battery in ampere-hours, or output, as from a generator.
One of the factors of wheel alignment. Viewed from the front of the car, it is the inward or outward tilt of the wheel. The top of the tire will
lean outward (positive camber) or inward (negative camber).
A shaft in the engine on which are the lobes (cams) which operate the valves. The camshaft is driven by the crankshaft, via a belt,
chain or gears, at one half the crankshaft speed.
A device which stores an electrical charge.
CARBON MONOXIDE (CO):
A colorless, odorless gas given off as a normal byproduct of combustion. It is poisonous and extremely dangerous in confined areas, building up slowly to toxic levels without warning if adequate ventilation is not available.
A device, usually mounted on the intake manifold of an engine, which mixes the air and fuel in the proper proportion to allow even
The forward or rearward tilt of an imaginary line drawn through the upper ball joint and the center of the wheel. Viewed from the sides, positive caster (forward tilt) lends directional stability, while negative caster (rearward tilt) produces instability.
A device installed in the exhaust system, like a muffler, that converts harmful byproducts of combustion into carbon dioxide and water vapor by means of a heat-producing chemical reaction.
Early center caps for automobiles were used to keeping dirt away from wheel bearings and spindle nut later just decorative.
A mechanical method of advancing the spark timing by using flyweights in the distributor that react to centrifugal force generated by the distributor shaft rotation.
The outward pull of a revolving object, away from the center of revolution. Centrifugal force increases with the speed of rotation.
A measure of the ignition value of diesel fuel. The higher the cetane rating, the better the fuel. Diesel fuel cetane rating is roughly comparable to gasoline octane rating.
The load-bearing underpart of a motor vehicle.
Any one-way valve installed to permit the flow of air, fuel or vacuum in one direction only.
The valve/plate that restricts the amount of air entering an engine on the induction stroke, thereby enriching the air/fuel ratio.
Bucking or jerking condition that may be engine related and may be most noticeable when converter clutch is engaged; similar to the
feel of towing a trailer.
A split steel snapring that fits into a groove to hold various parts in place.
A switch which protects an electrical circuit from overload by opening the circuit when the current flow exceeds a pre-deter- mined level. Some circuit breakers must be reset manually, while most reset automatically.
Any unbroken path through which an electrical current can flow. Also used to describe fuel flow in some instances.
Another circuit in parallel with the major circuit through which power is diverted.
An electrical circuit in which there is no interruption of current flow.
The non-insulated portion of a complete circuit used as a common potential point. In automotive circuits, the ground is composed of metal parts, such as the engine, body sheet metal, and frame and is usually a negative potential.
That portion of a circuit not at ground potential. The hot circuit is usually insulated and is connected to the positive side of the battery.
A break or lack of contact in an electrical circuit, either intentional (switch) or unintentional (bad connection or broken wire).
A circuit having two or more paths for current flow with common positive and negative tie points. The same voltage is applied to each load device or parallel branch.
An electrical system in which separate parts are connected end to end, using one wire, to form a single path for current to flow.
A circuit that is accidentally completed in an electricty
CLAMPING (ISOLATION) DIODES:
Diodes positioned in a circuit to prevent self-induction from damaging electronic components.
The swept volume in a cylinder above the piston remaining when it reaches TDC (top dead center).
A transparent layer which, when sprayed over a vehicle's paint job, adds gloss and depth as well as an additional protective coating
Mainly a pre digital Illegal operation by tampering with a vehicle's odometer reading to show less miles.
A spiral spring similar to a clock spring located between the steering wheel and column.
Part of the power train used to connect/disconnect power to the rear wheels.
The same as a fluid coupling. A fluid clutch or coupling performs the same function as a friction clutch by utilizing fluid friction and inertia as opposed to solid friction used by a friction clutch.
A coupling device that provides a means of smooth and positive engagement and disengagement of engine torque to the vehicle powertrain. Transmission of power through the clutch is accomplished by bringing one or more rotating drive members into contact with complementing driven members.
Vehicle deceleration caused by engine braking conditions.
COEFFICIENT OF FRICTION:
The amount of surface tension between two contacting surfaces; identified by a scientifically calculated number.
Part of the ignition system that boosts the relatively low voltage supplied by the car's electrical system to the high voltage required to fire the spark plugs.
COLD CRANKING AMPS (CCA)
The amount of current a battery can provide to start for around 30 seconds .
An assembly which includes both the intake and exhaust manifolds in one casting.
A device used in some fuel systems that routes fuel vapors to a charcoal storage canister instead of venting them into the atmosphere. The valve relieves fuel tank pressure and allows fresh air into the tank as the fuel level drops to prevent a vapor lock situation.
The part of the engine in the cylinder head where combustion takes place of the fuel/air mixture.
A gear consisting of two or more simple gears with a common shaft.
A gearset that has more than the three elements found in a simple gearset and is constructed by combining members of two planetary gearsets to create additional gear ratio possibilities.
A test involving removing each spark plug and inserting a gauge. When the engine is cranked, the gauge will record a pressure reading in the individual cylinder. General operating condition can be determined from a compression check.
The ratio of the volume between the piston and cylinder head when the piston is at the bottom of its stroke (bottom dead center) and when the piston is at the top of its stroke (top dead center).
An electronic control module that correlates input data according to prearranged engineered instructions; used for the management of an actuator system or systems.
An electrical device which acts to store an electrical charge, preventing voltage surges.
A radiator-like device in the air conditioning system in which refrigerant gas condenses into a liquid, giving off heat.
Any material through which an electrical current can be transmitted easily.
The connecting link between the crankshaft and piston.
CONSTANT VELOCITY JOINT:
Type of universal joint in a halfshaft assembly in which the output shaft turns at a constant angular velocity without variation, provided that the speed of the input shaft is constant.
CONSTINUOSLY VARIABLE TRANSMISSION (CVT)
Automatic type variable transmission that can change through a continuous range of gear ratios.
Continuous or complete circuit. Can be checked with an ohmmetec
The upper or lower suspension components which are mounted on the frame and support the ball joints and steering knuckles.
Ignition system which uses breaker points.
or as torque converter
The switching from hydrodynamic to direct mechanical drive, usually through the application of a friction element called the converter clutch.
Mixture of water and anti-freeze circulated through the engine to carry off heat produced by the engine.
An inhibitor in ATF that prevents corrosion of bushings, thrust washers, and oil cooler brazed joints.
An intermediate shaft which is rotated by a main-shaft and transmits, in turn, that rotation to a working part.
Occurs when the torque converter is operating at its greatest hydraulic efficiency. The speed differential between the impeller and the turbine is at its minimum. At this point, the stator freewheels, and there is no torque multiplication.
The lower part of an engine in which the crankshaft and related parts operate.
Engine component (connected to pistons by connecting rods) which converts the reciprocating (up and down) motion of pistons to rotary motion used to turn the driveshaft.
Part of the crankshaft attached to the engine's connecting rods and pistons that rotates in a main bearing.
The distance between the centerline of the crankshaft and the furthest offset of a big end journal.
bolted across the underside of a monocoque/unibody type motor vehicle,transverse to the main structure.
The weight of a vehicle without passengers or payload, but including all fluids (oil, gas, coolant, etc.) and other equipment speci-
fied as standard.
The flow (or rate) of electrons moving through a circuit. Current is measured in amperes (amp).
CURRENT FLOW CONVENTIONAL:
Current flows through a circuit from the positive terminal of the source to the negative terminal (plus to minus).
CURRENT FLOW, ELECTRON:
Current or electrons flow from the negative terminal of the source, through the circuit, to the positive terminal (minus to plus). CV-JOINT: Constant velocity joint.
The off-center movement of a rotating object that is affected by its initial balance, speed of rotation, and working angles.
see engine block.
The detachable portion of the engine, usually fastened to the top of the cylinder block and containing all or most of the combustion chambers. On overhead valve engines, it contains the valves and their operating parts. On overhead cam engines, it contains the camshaft as well.
In an engine, the round hole in the engine block in which the piston(s) ride up and down.