Automotive terms Modern (F)
Automotive Technical terms and abbreviations overview used in the industry, Guide and explanations.
The following are examples of Mid Modern technical terms F recommended for general use worldwide. For in-depth specific terms also see terms for historic vintage and specific areas such as Paint.
FAIL-SAFE (BACKUP) CONTROL:
A substitute value used by the PCMT to replace a faulty signal from an input sensor. The temporary value allows the vehicle to continue to be operated.
FAST IDLE:
The Speed Of the engine When the Choke is on. Fast idle
FEEDBACK:
A circuit malfunction whereby current can find another
FEELER GAUGE:
A blade, usually metal, of precisely predetermined thickness, used to measure the clearance between two parts.
FILAMENT:
The part of a bulb that glows; the filament creates high resistance to current flow and actually glows from the resulting heat.
FINAL DRIVE:
An essential part of the axle drive assembly where final gear reduction takes place in the powertrain. In RWD applications and north-south FWD applications, it must also change the power flow direction to the axle shaft by ninety degrees. (Also see axle ratio).
FIRING ORDER:
The order in which combustion occurs in the cylinders of an engine. Also the order in which spark is distributed to the plugs
FIRM:
A noticeable quick apply of a clutch or band that is considered normal with medium to heavy throttle shift; should not be confused with harsh or rough.
FLAME FRONT:
The term used to describe certain aspects of the fuel explosion in the cylinders. The flame front should move in a controlled pattern across the cylinder, rather than simply exploding immediately.
FLARE (SLIPPING):
A quick increase in engine rpm accompanied by momentary loss of torque; generally occurs during shift.
FLAT ENGINE:
Engine design in which the pistons are horizontally opposed. Porsche, Subaru and some old VW are common examples of flat engines.
FLAT RATE:
A dealership term referring to the amount of money paid to a technician for a repair or diagnostic service based on that particular service versus dealership's labor time (NOT based on the actual time the technician spent on the job).
FLAT SPOT:
A point during acceleration when the engine seems to lose power for an instant.
FLOODING:
The presence of too much fuel in the intake manifold and combustion chamber which prevents the air/fuel mixture from firing, thereby causing a no-start situation.
FLUID:
A fluid can be either liquid or gas. In hydraulics, a liquid is used for transmitting force or motion.
FLUID COUPLING:
The simplest form of hydrodynamic drive, the fluid coupling consists of two look-alike members with straight radial varies referred to as the impeller (pump) and the turbine. Input torque is always equal to the output torque.
FLUID DRIVE:
Either a fluid coupling or a fluid torque converter. (See hydrodynamic drive units.)
FLUID TORQUE CONVERTER:
A hydrodynamic drive that has the ability to act both as a torque multiplier and fluid coupling. (See hydrody-
namic drive units; torque converter.)
FLUID VISCOSITY:
The resistance of a liquid to flow. A cold fluid (oil) has greater viscosity and flows more slowly than a hot fluid (oil).
FLYWHEEL:
A heavy disc of metal attached to the rear of the crankshaft. It smoothes the firing impulses of the engine and keeps the crankshaft turning during periods when no firing takes place. The starter also engages the flywheel to start the engine.
FOOT POUND
(ft. lbs., lbs. ft. or sometimes, ft. lb.): The amount of energy or work needed to raise an item weighing one pound, a distance of one foot.
FREEZE PLUG:
A plug in the engine block which will be pushed out if the coolant freezes, Sometimes called expansion plugs, they protect the block from cracking should the coolant freeze.
FRICTION:
The resistance that occurs between contacting surfaces. This relationship is expressed by a ratio called the coefficient of friction
FRICTION, COEFFICIENT OF:
The amount of surface tension between two contacting surfaces; expressed by a scientifically calculated number.
FRONT END ALIGNMENT:
A service to set caster, camber and toe-in to the correct specifications, This will ensure that the car steers and handles properly and that the tires wear properly.
FRICTION MODIFIER:
Changes the coefficient of friction of the fluid between the mating steel and composition clutch/band surfaces during the engagement process and allows for a certain amount of intentional slipping for a good "shift-feel".
FRONTAL AREA:
The total frontal area of a vehicle exposed to air flow.
FUEL FILTER:
A component of the fuel system containing a porous paper element used to prevent any impurities from entering the engine through the fuel system. It usually takes the form of a canister-like housing, mounted in-line with the fuel hose, located anywhere on a vehicle between the fuel tank and engine.
FUEL INJECTION:
A system replacing the carburetor that sprays fuel into the cylinder through nozzles. The amount of fuel can be more precisely controlled with fuel injection.
FULL FLOATING AXLE:
An axle in which the axle housing extends through the wheel giving bearing support on the outside of the housing.
The front axle of a four-wheel drive vehicle is usually a full floating axle, as are the rear axles of many larger (1 ton and over) pick-ups and vans.
FULL-TIME FOUR-WHEEL DRIVE:
A four-wheel drive system that continuously delivers power to all four wheels. A differential between the
front and rear driveshafts permits variations in axle speeds to control gear wind-up without damage.
FULL THROTTLE DETENT DOWNSHIFT:
A quick apply of accelerator pedal to its full travel, forcing a downshift.
FUSE:
A protective device in a circuit which prevents circuit overload by breaking the circuit when a specific amperage is present. The device is constructed around a strip or wire of a lower amperage rating than the circuit it
is designed to protect. When an amperage higher than that stamped on the fuse is present in the circuit, the strip or wire melts, opening the circuit.
FUSIBLE LINK:
A piece of wire in a wiring harness that performs the same job as a fuse. If overloaded, the fusible link will melt and interrupt the circuit.
FWD:
Front wheel drive.
