Wrap-Up

Ready for Review

• Gasoline is produced from cracking crude oil into simpler hydrocarbon strings.
• The higher the octane level, the more resistant it is to pre-ignition.
• Winter blends of fuel that eliminate the ethanol content help with engine operation.
• Higher altitude can allow the engine to operate with a lower octane.
• Fuel that has been contaminated with water or alcohol may cause engine performance issues.
• The stoichiometric ratio of gasoline is 14.7:1.
• Ethanol is made from distilling organic material into alcohol.
• Ethanol has a higher octane rating that gasoline.
• Methanol is a simpler hydrocarbon that burns cleaner than gasoline.
• Flex fuel operation has software that can operate under both fuel strategies.
• CNG fuel requires a considerable amount of extra equipment to operate an engine on CNG.
• CNG is popular in flex fuel type vehicles as it operates well in the internal combustion engine.
• Propane is a simpler hydrocarbon chain which allows it to burn cleaner than natural gas.
• Propane is cheaper to operate than gasoline fuel.
• Synthetic fuels are derived from coal and other materials which can be refined into usable fuel.
• Fuel cells convert hydrogen fuel into electricity and water.
• Fuel cells require trained people to fill up the fuel cell.

Key Terms

compressed natural gas (CNG)  Methane compressed for onboard storage in cylinders.

Fischer-Tropsch process  A process that changes a mixture of carbon monoxide gas and hydrogen gas into liquid hydrocarbons.

fuel cell  An electrochemical device that uses hydrogen and oxygen to create electricity.

gasoline  A volatile, flammable liquid mixture of hydrocarbons, obtained from crude oil and used as fuel for internal combustion engines.

liquefied natural gas (LNG)  A cryogenic liquid produced from gaseous methane.

liquefied petroleum gas (LPG)  Gaseous fuel at atmospheric pressure; commonly referred to as propane.

Motor Octane Number (MON)  A rating that is more severe operation than might be incurred at high speed or high load.

Reid Vapor Pressure (RVP)  A measure of the volatility of gasoline.

Research Octane Number (RON)  A rating number that simulates fuel performance under low severity engine operation.

stoichiometry  The relationship between the relative quantities of substances taking part in a reaction or forming a compound.

Review Questions

1. Water in gasoline helps to thin it out to make it last longer.
   • True
   • False
2. What is the correct stoichiometric ratio for a gasoline engine?
   • 15.2:1
   • 16.3:1
   • 14.7:1
   • 13.5:1
3. CNG fuel usage decreases which of the following?
   • Power
   • Emissions
   • Options for engine design
   • Engine components
4. LNG is not used for consumer vehicles because:
   • A large amount of infrastructure is needed to refuel the vehicle.
   • They cannot handle refueling very well.
   • Political factors that will not allow the technology to prosper.
   • The fuel is not very efficient.
5. Altitude affects the amount of fuel that an engine needs because:
   • The thinner air requires less fuel to maintain the 14.7:1 ratio.
   • The thinner air requires more fuel to maintain the 14.7:1 ratio.
   • Nothing needs to be done to maintain the proper ratio.
   • The thicker air requires less fuel to maintain 14.7:1 ratio.
6. All of the following statements about automotive fuels are true EXCEPT:
   • Ethanol is created by distilling organic material into ethyl alcohol.
   • Gasoline is classified by octane number.
   • Synthetic fuels can be made from coal or other hydrocarbon materials.
   • Methanol is used extensively in production automobiles in the United States.
7. What is the key difference between winter and summer blends of fuel?
   • Winter blends increase the ethanol content to help with thinning out the petroleum-based fuel.
   • The octane level is different.
   • Winter blends remove the ethanol so the fuel has more heat capacity.
   • Winter fuel is mixed with antifreeze so that it will not freeze.
8. Propane fuel is kept in a liquid form and when it is introduced into the fuel system it expands at:
   • 240 times its liquid volume
   • 580 times its liquid volume
   • 270 times its liquid volume
   • 420 times its liquid volume
9. When looking at a misfire on an engine the technician should check the fuel quality. What is the technician looking for?
   • Octane level
   • Heat capacity level
   • Fuel contaminated by another liquid
   • Liquid state of the fuel
10. Fuel cells work with hydrogen, oxygen, and what other component?
    • Catalyst
    • Water
    • Metal
    • Gasoline

ASE Technician A/Technician B–Style Questions

1. Technician A states that using ethanol will increase the fuel mileage of the engine. Technician B says the higher the octane of the fuel, the more resilient it is to pre-ignition. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
2. Technician A says that ethanol is made out of biological material that is distilled into alcohol. Technician B states that propane and natural gas are the same things. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
3. Technician A states a fuel cell produces more emissions than an internal combustion engine. Technician B states that flex fuel vehicles operate the same as a conventional vehicle without any modification. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
4. Technician A says that octane determines how much the gasoline can resist pre-ignition. Technician B states that methanol is the same thing as ethanol because they are both made out of organic material. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
5. Technician A says water or alcohol dilution can cause fuel to become unusable in an internal combustion engine. Technician B states that CNG-powered vehicles produce less emissions than gasoline-powered vehicles. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
6. Technician A says that octane rating is not important to the operation of the internal combustion engine. Technician B states that flex fuel vehicles can run on two types of fuels. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
7. Technician A says that synthetic fuels can be derived from a large source of materials that are not petroleum based. Technician B states that cracking the hydrocarbon strings to create gasoline requires high pressure and heat. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
8. Technician A says alcohol-based fuel usually has a higher octane than conventional petroleum-based fuel. Technician B states that because ethanol is produced from organic plant stock it has a more stable production environment. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
9. Technician A states that when diagnosing an engine, you must be aware of the type of fuel being used to understand how it reacts to heat and pressure. Technician B says to create gasoline the cracking process has to break down the hydrocarbon molecule strings. Who is correct?
   • Tech A
   • Tech B
   • Both A and B
   • Neither A nor B
10. Technician A says propane can be used on a conventional engine with minor modifications to the engine fuel system. Technician B says the production of ethanol can only be done with a petroleum base. Who is correct?
    • Tech A
    • Tech B
    • Both A and B
    • Neither A nor B