Engine Performance (A8)第 98 / 120 题
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
解析
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.
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