Exam 30: Electronic Fuel Injection

The high-pressure fuel pump used in GDI ( gasoline direct injection)is driven by the ____________________.

Which of the following is NOT representative of sequential fuel injection systems?

Technician A says pulsation dampers reduce the pressure pulsations caused by the rapid opening and closing of the fuel injectors. Technician B says the damper helps to reduce fuel noise and maintains pressure during engine cooldown. Who is correct?

The most important sensor in the fuel management system is _____.

Technician A says the air/fuel ratio of a GDI (gasoline direct injection)engine can be as high as 60 to 1. Technician B says because the air/fuel ratios are so lean, GDI engines require lower compression ratios to prevent detonation. Who is correct?

Which of the following is NOT a component of a throttle-by-wire system?

In TBI, MFI, and SFI systems, the fuel pressure must be high enough to prevent fuel ____________________.

The mass airflow (MAF)sensor measures changes in the intake manifold pressure that result from changes in engine load and speed.

A speed-density EFI system computer determines the amount of air entering the engine from the ____________________ sensor and engine rpm input signals.

Technician A says an SFI is more efficient than an MFI injection because fuel is injected only when the intake valve is open, so the fuel can't condense when the intake valve is closed. Technician B says an MFI injection system can shut down the injector for a misfiring cylinder, preventing catalytic converter overheating. Who is correct?

The ____________________ in a TBI system is designed to provide a constant pressure on the fuel injector throughout the range of engine loads and speeds.

Technician A says TBI systems use top fuel-feeding injectors. Technician B says PFI systems use bottom fuel-feeding injectors. Who is correct?

Today the most commonly used EFI system is the mass airflow (MAF)system which relies on a MAF sensor that directly measures the amount of intake air.