Exam 39: Fuels and Alternative Fuels

Diesel fuels contain some paraffin (wax). In very cold weather, the paraffin can separate from the fuel. This is called the ____________________.

Unlike preignition, detonation does not produce a knocking sound, so the impending damage is not apparent until it is too late.

While having a discussion, Technician A says that the noise from spark knock is caused by the vibration of the combustion chamber walls. Technician B says that it is caused by low volatility. Who is correct?

All of the following statements are true EXCEPT:

Which of the following statements is LEAST-Likely true?

When a gasoline engine continues to run even after the ignition key is turned off, this is called ____________________.

What are some of the problems that can occur as a result of vapor lock?

While having a discussion, Technician A says that carbonaceous deposits are caused when oil and heat come together. Technician B says that carbonaceous deposits are from fuel. Who is correct?

Although biodiesel is cleaner burning than petroleum diesel, pure biodiesel (B100) requires fuel system modifications on pre-1994 diesel engines.

A car's ____________________ on the highway is a symptom of a lean condition.

What are the disadvantages of LPG?

All of the following statements are true EXCEPT:

Water is an enemy to diesels and must not be allowed to accumulate in the fuel system.

What are some of the possible causes of preignition?

What is the difference between the following two grades for automotive diesel fuel: Grade number 1-D and Grade number 2-D?

Gasoline can be refined so it will not knock as easily. This fuel has a high ____ value.

Crude oil is a variable combination of large and small hydrocarbons together with petroleum gas, hydrogen sulfide, and water.

With gasoline octane ratings, the lower the octane number, the more resistant the fuel is to knocking.

What are the results of low volatility?

____________________ is a measure of how easy a fuel evaporates.