ASE A8 Engine Performance Practice Test

6. An engine has a rich air-fuel ratio. There is excessive resistance found at point A in the schematic diagram above. All of the following statements regarding this circuit are true EXCEPT:
- A. Point A is the ground connection for the (NTC) negative temperature coefficient sensor.
- B. Too much resistance at point A will result in delayed torque converter engagement.
- C. Too much resistance at point A will result in delayed engine cooling fan operation.
- D. The ECM provides a 12-volt reference signal.
7. An engine is misfiring and stumbling at idle. Which of the following is MOST likely causing this condition?
- A. A faulty (TPS) throttle position sensor.
- B. A faulty (IAT) intake air temperature sensor.
- C. A faulty (EGR) exhaust gas recirculation valve.
- D. A faulty (ECT) engine coolant temperature sensor.
8. The turbocharger's wastegate diaphragm is leaking. This leak will result in:
- A. An underboost condition.
- B. An overboost condition.
- C. Low intake manifold pressure.
- D. Oil consumption.
9. An engine with (SFI) Sequential Fuel Injection has poor fuel mileage. A fuel pressure test indicates high fuel pressure at the fuel rail. Which of the following is LEAST likely to result in this condition?
- A. A kink in the fuel return line.
- B. A ruptured fuel regulator diaphragm.
- C. A clogged fuel injector.
- D. A disconnected fuel regulator vacuum hose.
10. An engine with sequential fuel injection is scanned, and the LTFT is 24% at idle. This percentage decreases when the engine speed is increased to 1500 RPM. Which of the following will result in this condition?
- A. High fuel pressure.
- B. A disconnected vacuum hose.
- C. A ruptured fuel pressure regulator diapragm.
- D. A dripping fuel injector.