Car Tuning Car Maintenance 4 — Questions and Answers
Question 1: What is the purpose of wheel balancing when installing new tires?
- To align the steering geometry
- To distribute weight evenly around the wheel/tire assembly and prevent vibration (Correct answer)
- To set tire pressure
- To measure tread depth
Correct answer: To distribute weight evenly around the wheel/tire assembly and prevent vibration
Uneven weight distribution in a wheel/tire assembly causes vibration at speed; balancing weights correct this.
Question 2: Which engine oil additive property is indicated by the 'W' in a rating like 5W-30?
- Weight of the oil
- Winter cold-flow performance (Correct answer)
- Water resistance
- Wear protection rating
Correct answer: Winter cold-flow performance
The 'W' stands for Winter and describes how well the oil flows at low temperatures, affecting cold-start protection.
Question 3: Why is it important to torque lug nuts in a star pattern?
- To make removal easier later
- To ensure even clamping force and prevent brake rotor warping (Correct answer)
- To center the wheel visually
- Star pattern is traditional but has no technical benefit
Correct answer: To ensure even clamping force and prevent brake rotor warping
Tightening opposite lugs alternately distributes clamping load evenly, preventing the wheel from seating at an angle and warping the rotor.
Question 4: What does it mean when your power steering fluid appears dark brown or black?
- It has been dyed for identification
- The fluid is heavily oxidized and contaminated and should be flushed (Correct answer)
- It has more viscosity than fresh fluid
- The color change is normal after 1,000 miles
Correct answer: The fluid is heavily oxidized and contaminated and should be flushed
Dark power steering fluid indicates oxidation and rubber seal degradation, which can damage the rack and pump if not flushed.
Question 5: A car pulls to one side during braking. What is the most likely cause?
- Low engine oil
- A sticking brake caliper or uneven brake pad wear (Correct answer)
- Mismatched tire brands
- A failing alternator
Correct answer: A sticking brake caliper or uneven brake pad wear
A stuck caliper applies braking force on one side only, creating an imbalance that pulls the vehicle toward the dragging brake.
Question 6: What is the purpose of a catch can in a performance engine build?
- To store extra engine oil
- To trap oil mist from crankcase gases before they re-enter the intake (Correct answer)
- To filter fuel before the injectors
- To cool the intake charge
Correct answer: To trap oil mist from crankcase gases before they re-enter the intake
Oil vapor from the PCV system can coat intake valves with carbon deposits; a catch can intercepts and collects this mist.
Question 7: When should you replace your car's timing belt rather than waiting for symptoms?
- Only after you hear a squealing noise
- At the manufacturer's specified mileage interval, typically 60,000–105,000 miles (Correct answer)
- Every 150,000 miles regardless of manufacturer
- Only when oil leaks onto it
Correct answer: At the manufacturer's specified mileage interval, typically 60,000–105,000 miles
Timing belts fail without warning, and a break on an interference engine can destroy valves and pistons, so replacement before failure is critical.
Car Tuning Car Maintenance 4
What is the purpose of wheel balancing when installing new tires?