NAPA Cheat Sheet 2026

The 30 highest-yield NAPA facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What does a large positive long-term fuel trim (LTFT) value indicate? → The ECM is adding fuel to compensate for a lean condition
2. What should you always do before lifting a vehicle? → Secure the lift points
3. A technician is performing a brake fluid flush. What is the primary reason for periodically replacing brake fluid? → The fluid is hygroscopic and absorbs moisture, lowering its boiling point.
4. Which tool is commonly used to diagnose electrical issues? → Multimeter
5. When bleeding the brakes on most non-ABS passenger vehicles, what is the generally accepted sequence? → Start with the wheel furthest from the master cylinder and work to the closest.
6. What does ABS stand for? → Anti-lock Braking System
7. A vehicle is brought into the shop with a complaint of a "spongy" or "soft" brake pedal. Which of the following is the MOST common cause of this symptom? → Air in the hydraulic brake lines
8. When servicing an A/C system containing R-1234yf refrigerant, which of the following is a critical difference compared to servicing an older R-134a system? → R-1234yf is mildly flammable and requires dedicated, certified service equipment.
9. What is the typical operating fuel pressure for a port fuel injection (PFI) system? → 35–65 PSI
10. What is the correct method for testing a fuel injector's electrical coil? → Measure resistance across the injector terminals with an ohmmeter
11. What is the most likely result of a clogged fuel injector? → A lean condition and potential engine misfire
12. Why should tools be returned to their proper place after use? → To prevent loss and ensure safety
13. Why is it important to wear safety glasses in the shop? → To prevent eye injury
14. Why is it important to address check engine light issues promptly? → It may damage the catalytic converter
15. Which emission system recirculates exhaust gases to lower combustion temperature? → EGR system
16. What is the purpose of a torque wrench? → To measure torque accurately
17. Which system uses sensors to monitor exhaust gases? → Emissions control system
18. Which of the following symptoms is MOST commonly associated with a worn universal joint (U-joint) on a rear-wheel-drive vehicle's driveshaft? → A clunking sound when shifting from Drive to Reverse
19. Which engine component is directly driven by the crankshaft? → Camshaft
20. Which suspension type uses a single spring and damper assembly? → MacPherson strut
21. Which part connects the suspension system to the wheel hub? → Control arm
22. What does evaluating an injector's spray pattern reveal about its condition? → Whether the injector atomizes fuel into a proper mist or streams and dribbles
23. What could cause a spongy brake pedal? → Air in brake lines
24. What is the purpose of a fuse in a vehicle? → Protects circuits from overload
25. Which of the following BEST describes the function of a planetary gear set in an automatic transmission? → It uses a sun gear, planet gears, and a ring gear to create various gear ratios.
26. Which sensor primarily calculates air mass in a speed-density fuel injection system? → Manifold Absolute Pressure (MAP) sensor
27. What symptom may indicate worn brake pads? → Squeaking noise when braking
28. What is the main role of a catalytic converter? → Reduces harmful emissions
29. Which system ensures the engine operates at ideal temperature? → Cooling system
30. Automatic Transmission Fluid (ATF) serves multiple purposes. Besides lubrication and acting as a hydraulic fluid, what is another critical function of ATF? → To provide cooling and heat dissipation for transmission components