程设计投资控制的中心思想是采取预控措施，促使设计在满足质量和使用功能的前提下，不超过设计投资并尽可能地实现节约。主要控制的方法包括（）。

A.Low compression pressure and high exhaust temperature

B.Low firing pressure and high exhaust temperature

C.Low compression pressure and low exhaust temperature

D.Low firing pressure and low exhaust temperature

High firing pressures and low exhaust temperature in a diesel engine may resultfrom().

A.decreased piston to cylinder head clearance

B.increased exhaust system back pressure

C.early fuel injection timing

D.low scavenge air temperature

Early injection timing is indicated by ______.

A.high exhaust temperature and low firing pressure

B.high exhaust temperature and high firing pressure

C.low exhaust temperature and low firing pressure

D.low exhaust temperature and high firing pressure

A.lower than normal cylinder pressure and low exhaust temperature

B.lower than normal cylinder pressure and high exhaust temperature

C.higher than normal cylinder pressure and low exhaust temperature

D.higher than normal cylinder pressure and high exhaust temperature

An indication of a diesel engine air intake being partially clogged, is _____.

A.low firing pressure and low exhaust temperatures

B.low firing pressure and normal exhaust temperatures

C.high firing pressure and low exhaust temperatures

D.high firing pressure and high exhaust temperatures

A.decreased piston to cylinder head clearance

B.increased exhaust system back pressure

C.early fuel injection timing

D.low scavenge air temperature

A.Improper fuel rack positioning

B.Lengthy opening of the exhaust valve

C.Excessively early injection timing

D.Extended light load operation

A.increase scavenge air pressure

B.reduce fuel booster pump pressure

C.adjust the fuel rack

D.retard fuel injector timing

A.low exhaust temperature

B.low exhaust pressure

C.mechanical knock in each cylinder

D.black or gray exhaust smoke