A Brief Glossary of Auto Repair Terms
When technicians or service advisors start using jargon-heavy automotive terminology, it can get confusing pretty quickly. At Allen Rubber in Philadelphia, PA, we try to be as direct and clear as possible with our customers, so here's a brief rundown of terms you might hear:
Air filter: It's important to keep pollen, dust and other tiny particles from entering your engine's fuel system. The air filter traps these small bits before they can make their way in, using a pleated-paper or fabric medium (sometimes saturated with a special oil).
A/C Compressor: Like your refrigerator at home, your car's air conditioner relies on a cycle of evaporation and condensation of a gas refrigerant to provide cooling. The refrigerant is turned back into a liquid again when it passes through the compressor, a pump (driven by the engine) that puts the refrigerant under pressure. The compressor is the heart of your A/C system.
Belt: Your vehicle's air conditioning compressor, power steering pump, water pump, alternator and other accessories are all powered by a rubber belt that's driven by the engine's crankshaft. Older vehicles had separate belts for each accessory, but from the 90s on engines have used a continuous "serpentine belt" that's routed to pulleys on all accessories. This lowers parasitic drag on the engine and saves space under the hood, since older systems had to have all the pulleys offset from each other to make room for the belts.
Diagnostics: Since the early 90s, engines have been designed with a processor that controls fuel metering, transmission shift points, power, emissions and other drivability factors. The processor takes information from sensors around the engine and transmission; when a sensor is sending information that is outside of norms, it registers a trouble code in the processor, illuminating the Check Engine lamp. From there, a technician can connect a scanner/code reader to the processor's diagnostic port and quickly access the information which will point him to the problem.
PCM: Related to engine diagnostics, the PCM is your engine's Powertrain Control Module. It's the processor that controls the engine functions mentioned above and stores trouble codes if needed. The PCM is the brains of your vehicle's electronics.
Sludge: If left too long without being changed, motor oil starts to collect acids, water vapor, carbon and grit from the combustion process. These contaminants can form accumulations of sludge on bearings and other internal moving parts, shortening engine life.
Wheel alignment: These are the angles of the front wheels that affect your car's handling and steering response. The angles are toe-in, an inward skew of a wheel as seen from above; toe-out, an outward skew of the wheel as seen from above; camber, the wheel's inward or outward tilt as seen from the front; and caster, the fore-and-aft positioning of the wheel.
Don't go into an auto repair shop uninformed...it's good to at least have some familiarity of what's being discussed when there's a problem with your car. And if you're noticing any issues with your own vehicle, we hope you'll make an appointment with us at Allen Rubber in Philadelphia, PA!