Auto-Sector Interview Preparation

Converts fuel energy into mechanical energy to drive the wheels.

Cools the engine coolant by dissipating heat to the surrounding air.

Lubricates moving parts, reduces friction and wear, and helps cool and clean the engine.

A component that ignites the air-fuel mixture in a petrol engine combustion chamber.

Engages and disengages engine power to the gearbox so gears can be changed.

Petrol uses spark ignition; diesel uses compression ignition.

Stores electrical energy to start the engine and run electricals when the engine is off.

Generates electricity to charge the battery and run electricals while the engine runs.

To slow or stop the vehicle by converting kinetic energy into heat through friction.

Disc brakes and drum brakes.

The grooved rubber pattern that grips the road and channels away water.

With a gauge when tyres are cold, compared against the manufacturer specification.

To absorb road shocks and keep the tyres in contact with the road for comfort and control.

A damper that controls spring movement to reduce bouncing.

To clean the air entering the engine, preventing dust and grit from causing wear.

To remove dirt and impurities from fuel before it reaches the engine.

A fluid that regulates engine temperature and prevents freezing or overheating.

Revolutions per minute, how many times the crankshaft turns each minute.

The system that transfers engine power to the wheels at different speed and torque ratios.

Manual needs the driver to shift gears using a clutch; automatic shifts gears itself.

Adjusting wheel angles to specification for even tyre wear and straight tracking.

Adding weights so a wheel and tyre rotate without vibration.

To carry away and quieten burnt gases and reduce emissions.

An exhaust device that converts harmful gases into less harmful ones.

Anti-lock Braking System.

To tighten fasteners to a specified torque value.

Measuring voltage, current and resistance in electrical circuits.

To synchronise the rotation of the crankshaft and camshaft.

To circulate coolant through the engine and radiator.

A valve that regulates coolant flow based on engine temperature.

A safety device that breaks the circuit during excess current to protect components.

The recommended distance or time between scheduled maintenance.

Abnormal combustion that produces a knocking or pinging sound.

Maintains system pressure and raises the boiling point of the coolant.

A service is scheduled preventive maintenance; a repair fixes a specific fault.

To check the engine oil level.

To drive accessories such as the alternator, water pump and AC compressor.

Old oil loses lubrication quality and collects contaminants, leading to engine wear.

To illuminate the road and make the vehicle visible at night.

To warn other road users with an audible signal.

Intake, compression, power and exhaust strokes complete one combustion cycle over two crankshaft revolutions.

MPFI injects fuel into the intake port; direct injection sprays fuel straight into the cylinder.

Low coolant, a faulty thermostat, a failed water pump, a blocked radiator or a broken fan.

On-Board Diagnostics II, a standard port and system to read fault codes and live engine data.

Check fuel supply, spark or ignition, and ECU and sensor inputs systematically.

Check battery charge, terminals, starter motor, ignition switch and fuses.

Misalignment, imbalance, incorrect pressure or worn suspension components.

To recirculate some exhaust gas into the intake, lowering combustion temperature and NOx.

Random or multiple cylinder misfire.

Open the bleeder valves to expel air while topping up fluid, because air makes the pedal spongy.

Air in the lines, low fluid, worn pads or a failing master cylinder.

Sensors detect wheel lock and the modulator rapidly pulses brake pressure to keep grip.

It measures exhaust oxygen so the ECU can fine-tune the air-fuel ratio.

About 14.7 to 1 by mass.

Measure with a feeler gauge at TDC and adjust shims or tappets to specification.

Coolant entering combustion from a head gasket fault, or briefly condensation on a cold start.

Engine oil burning in the combustion chamber from worn rings or valve seals.

A rich mixture, meaning too much fuel or too little air.

It uses exhaust gas to spin a compressor that forces more air in for more power.

The delay before the turbo spools up and delivers boost.

A high-pressure rail feeds electronically controlled injectors for precise multiple injections.

Independent lets each wheel move separately; a rigid axle links both wheels together.

Measure battery voltage with the engine running; about 13.8 to 14.5 volts indicates charging.

Current draw with everything switched off; it is traced by measuring current and pulling fuses.

To vent crankcase blow-by gases back into the intake, reducing emissions and pressure.

Uneven pad wear, a stuck caliper or a hydraulic imbalance.

Wheel imbalance, a bent rim or worn suspension and steering parts.

It allows the driven wheels to rotate at different speeds while turning.

Hydraulic uses a pump and fluid pressure; electric uses a motor for assistance.

It measures intake air mass so the ECU can meter the correct amount of fuel.

Connect to the OBD-II port and monitor parameters such as RPM, coolant temperature, fuel trims and sensor outputs.

A protective state where the ECU limits performance after detecting a fault.

Short-term is instant correction; long-term is the learned average adjustment.

Connect the positives first, then negative to a ground point on the dead car, start it, then remove leads in reverse.

Oil and filter change, fluid levels, brakes, tyres, belts, lights and a diagnostics scan.

Check fuel pressure and delivery under load, coil and plug condition, and intake leaks; log freeze-frame data and fuel trims.

Look for coolant loss, white smoke, oil-coolant mixing and overheating, then confirm with a combustion-leak test or compression and leak-down test.

Apply compressed air to a cylinder at TDC; air escaping into the intake, exhaust, crankcase or coolant pinpoints valve, ring or gasket faults.

Check tyre pressure, air and fuel filters, oxygen sensor ageing, fuel trims, dragging brakes and driving pattern.

Faulty glow plugs, low compression, injector timing or leakage, or low-cetane fuel.

Reproduce the conditions, wiggle-test harnesses, check grounds and connectors, and monitor voltage drop across the circuit.

Under load it reveals high-resistance connections that a no-load continuity test would miss.

Inspect caliper slide pins, piston seizure, rotor condition, driving habits and pad quality.

Likely a failing cooling fan or fan clutch, since airflow is lost at low speed.

Check OBD port power and ground, the CAN bus wiring and module power, and look for a shorted module on the bus.

Run a compression and leak-down test, check the PCV, inspect valve seals and check the turbo seals.

It indicates a lean condition; suspect vacuum or intake leaks, weak fuel delivery or a faulty MAF.

A diesel particulate filter traps soot and regenerates by burning it; short trips and faults prevent regeneration and clog it.

Via a scan tool under safe conditions when passive and active regeneration fail and soot load is high.

Measure key-off current after modules sleep, pull fuses one by one to isolate the circuit, then test the component.

Check fluid level and condition, scan for codes, test line pressure and assess clutch and band wear.

Excess heat, low octane, a lean mix, carbon or wrong timing; correct fuel quality, cooling and timing and clean carbon.

Use a smoke machine on the EVAP system and inspect the gas cap, purge and vent valves and lines.

Test warm with the throttle open; readings should be within about ten percent of each other.

Scan the ABS module codes and check wheel-speed sensors, tone rings, wiring and the module.

Read hybrid system codes, check high-voltage battery state of health, cooling and the inverter, while observing HV safety.

Check refrigerant charge, compressor clutch cycling, condenser airflow, pressure switches and electrical control.

De-energise per manufacturer steps, use insulated PPE and tools, verify zero voltage and follow lockout.

Monitor live data for misfire counts and check the IAC or throttle body, vacuum leaks, injector balance and ignition.

Do not just clear codes; identify the failing component using freeze-frame data, live data and pinpoint tests, then verify the repair under the original conditions.