Idle-Up System
NOTE:
Ensure coolant temperature sensor is operating properly before checking idle-up system. For sensor testing, see ENGINE SENSORS & SWITCHES.
- Remove idle-up system Vacuum Switching Valve (VSV), located near end of valve cover (Tercel) on passenger's side.NOTE: The VSV may also be identified by appropriate illustration in THEORY/OPERATION article in the ENGINE PERFORMANCE Section or wire color. See appropriate wiring diagram in WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section.
- Using ohmmeter, measure resistance between VSV electrical terminals. Replace VSV if resistance is not 37-44 for Tercel. Check that no continuity exists between each electrical terminal and VSV body.
- Test VSV by applying air pressure to designated area and checking air passage, and then applying battery voltage and retesting. See Fig 1. Replace VSV if defective.