A diesel engine cooling water system with a pH factor of 30 indicates a condition of （）.

A.cold corrosion of the nozzles
B.fuel viscosity for better atomization
C.carbon accumulation on the nozzles
D.fuel detonation in the cylinders

A.the size of the holes in the fuel nozzle
B.timing of the pump
C.supply pressure to the pump
D.shape of the combustion chamber

A.fuel injectors
B.exhaust valves
C.intake valves
D.all of the above