Engine Performance (A8)Pregunta 98 de 120
Technician A says the MAF sensor measures the mass of air entering the engine so the PCM can meter fuel. Technician B says a dirty MAF can cause hesitation and fuel-trim errors. Who is correct?
a.Neither A nor B
b.Technician A only
c.Technician B only
d.Both A and B
Explicación
The MAF sensor measures intake air mass so the PCM meters the correct fuel quantity, and a dirty or faulty MAF causes incorrect fueling, hesitation, and trim errors. Both technicians are correct. Diagnosis includes cleaning or replacing it and checking for unmetered air leaks.
Practica las 120 preguntas gratis — sin registro.
Preguntas relacionadas de este tema
- Technician A says a vacuum leak causes a rich condition. Technician B says a vacuum leak adds unmetered air and causes a lean condition, especially at idle. Who is correct?
- Technician A says a positive long-term fuel trim of +20 percent means the PCM is adding fuel to correct a lean condition. Technician B says positive trim means the engine is running rich. Who is correct?
- Technician A says a rich air-fuel mixture can raise tailpipe CO and HC. Technician B says the oxygen sensor helps the PCM keep the mixture near stoichiometric. Who is correct?
- A P0420 code (catalyst efficiency below threshold) most often indicates:
- In a modern coil-on-plug ignition system, each coil:
- A knock sensor allows the PCM to:
Última revisión: · proceso editorial
Equipo Editorial de PrepPass · Verificado con ASE Automobile Certification Series (A1–A8) · Cómo revisamos