Automotive General Services Technician Model

Units:

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Lesson Plan Industry Sector
Transportation

Lesson Plan Originally Created By: Richard Williams

**5 Gas Analysis (updated) by Richard Williams

Part of Unit: Engine Performance

Lesson Plan Overview / Details

This is an introductory lesson to the five gases exhausted from the internal combustion gasoline engine and their relationship to the engine powertrain management system.

Lesson Time

Lecture
120 Minutes
Demonstration
60 Minutes
Lab
180 Minutes
Closure
30 Minutes

Standards

California Career and Technical Education Standards

California Academic Content Standards (Reinforced)

Objectives and Goals

This lesson is intended to introduce the automotive students to the five commonly measured exhaust gases of the internal combustion gasoline engine and their testing. It will also cover their relationships to other aspects of the internal combustion engine and its power-train management systems. The students will receive a lecture and demonstration on the five gasses and then practice, in a group environment, what they have learned. In addition, the student will practice all safety procedures noted. In conclusion the students will meet in a classroom environment to discuss what they have learned and experienced.

Activities in this Lesson

  • Prerequisite - Other

    A week before this lesson, the students will be given two documents (found in resources) to read to prepare them for class.

  • Opening Question - Hooks / Set

    Opening question:

    As the students enter the classroom, they will see a question I have written on the white board:

    "What can the exhaust of the gas engine tell us?"

    I let them think about this while I take roll and complete any other hosekeeping tasks required. Once they are settled, I’ll field answers from the class.  Answers usually are:
    “It’s running rich or lean” or  “It’s got a misfire."

    I then ask them to think of the medical field and pose this question.

    "Why does the doctor ask you to pee in the cup?"

    I’ll then tell them it’s to find out what you have ingested and how you body, the human engine, used it. Are you getting everything you can out of it or are you wasting some of it? I then tell them this is basically why we analyze engine exhaust.

  • Classroom Power Point Lecture - Lecture

    I now lecture from the classroom PowerPoint. Students are encouraged to take notes. I will stop at key points during the presentation and ask the students questions to ensure they are understanding the material presented to them.

    • 5 Gas classroom Power Point [ Download ] 5 Gas classroom Power Point
  • Shop Demonstration on the use of a Five Gas Analyzer - Demo / Modeling

    I will now have the students watch me in the shop where I have prepared a vehicle to simulate certain common conditions you may encounter when using a 5 gas analyzer to diagnose a gasoline engine's exhaust. I have set up two 32" monitors to a 5 gas analyzer to enable all (appx. 25) students to easily view the demonstration.

  • Group Lab - Lab / Shop

    At this time I issue a vehicle to each group of students (2 to 4) and instruct them to follow lab sheet and analyze the exhaust. They are also instructed to log on to smogsite.com (http://www.smogsite.com/calculators.html#lambda), find and use a lambda calculator and record on back of lab sheet. They will also be encouraged to manipulate the exhaust gasses to find a particular result.

    For example:

    "If I introduce propane into the intake, which gases will change, by how much and in which direction?"

    They are also encouraged to connect an appropriate scan to a Digital Storage Oscilloscope to monitor O2 sensors as well as Long & Short Term Fuel Trim for conclusions that will later be discussed in the classroom.

    I will also visit and interview each group throughout the lab session.

  • Classroom Discussion - Closure

    I will now have students return to class room and each group of students will share their experiences. I use their comments to add additional information and will also review some of the PPT slides that are appropriate.

Assessment

Assessment Types:
Interviews, Teacher-Made Test, Observations,

I will now have them take a short six question test to check their knowledge. Eventually the students will receive questions on a more formal test covering this material.

Materials/Resources: Prerequisite