AUT-101 Mid Term

External combustion means that the fuel is being burned outside of the engine, while internal combustion means the fuel is burned inside of the engine. 

• True

• False

Compression loss results in low compression pressures and excessive amounts of blow-by gases into the crankcase, leading to ___________. 

• Reduced combustion efficiency and less engine power 

• Greater vehicle emissions 

• Poor fuel economy 

• All of the above 

The ratio of the crank gear to the camshaft gear(s) is: 

• 2 to 1 

• 4 to 1 

• 3 to 1 

• 1 to 1 

The reed valve is made of _______ and can be attached to the crankcase or to the inlet port. 

• Spring metal 

• Heavy plastic 

• Aluminum alloy 

• Cast iron 

A visual inspection of the engine assembly for leaks will affirm the ability of the _______ to contain each of the engine's fluids. 

• Seals 

• Gaskets 

• Both A and B 

• Neither A nor B 

A _______ pumps air into the engine's cylinder and measures the percentage of air that is leaking from that cylinder. 

• Compression tester 

• Pressure transducer 

• Cylinder leakage tester 

• Data link connector (DLC) 

Technician A says that low compression on a single cylinder will cause an engine not to start. Technician B says that low compression on a single cylinder will affect the engine's cranking sound. Who is correct? 

• Technician A  

• Technician B

• Both A and B 

• Neither A nor B 

When performing a cranking sound diagnosis, Technician A says that all engines may be prevented from starting by holding the throttle wide open while cranking. Technician B says that an engine may be disabled by removing the fuel pump fuse or relay (if equipped). Who is correct?

• Technician A 

• Technician B 

• Both A and B 

• Neither A nor B 

When testing intake manifold vacuum, the gauge reads normal at idle, but reads very low when the engine is held steady at 2,500 rpm. Technician A says this indicates worn valve guides. Technician B says this indicates a restricted exhaust system. Who is correct? 

• Technician A 

• Technician B 

• Both A and B 

• Neither A nor B 

If the engine has port fuel injectors that are accessible, disconnecting the electrical connector from each injector one at a time will shut off the fuel to that particular cylinder

• True

• False