Activity Industry Sector

Activity Originally Created By: MaryRose Lovgren

Understanding Vacuum / Driving Conditions

Part of Lesson Plan: Vacuum Testing / Driveability (updated) by Michael Fleming

Activity Overview / Details

Transition to direct instruction using the white board.  If you are an Engine Performance and Emissions Diagnosis class, I like to first list the smog systems that use vacuum (Intake & Ported).  For Iintake list PCV, EVAP, AIR, TAC. For ported, list EGR.

See student notes: Next draw four large columns and divide them in half. On the top draw four basic driving conditions: stop, part throttle, wide open throttle WOT, and deceleration (one in each column). The whole time, describe the loads placed on the motor and expected vacuum, engine rpm, and throttle position. Then on the second row, go back and list these conditions for each picture. Last I draw a throttle body and two vacuum gauges (Intake & Ported). In each column have the students start to anticipate what position the throttle is in and what is the expected vacuum (note that the video did not sho ported vacuum, and that it only has vacuum at part throttle).

You will find that the students start to feed you the information as you draw and they begin to predict what is happening.

Materials / Resource