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Idle Speed: Notes

  1. Ensure air cleaner and all electrical connections and emission hoses are properly installed. Warm engine to normal operating temperature. Turn engine off. Ensure all accessories are off.
  2. Remove cover from diagnostic cover, located on left strut tower. Connect tachometer to specified terminal of diagnostic connector and to the battery. See Figure .
    CAUTION: DO NOT ground tachometer terminal in diagnostic connector, as grounding terminal could result in ignitor or ignition coil damage.
  3. Install jumper wire between terminals E1 and "T" or TE1 of diagnostic connector. See Figure . Start engine and note idle speed. Idle speed should be within specification. See IDLE SPEED SPECIFICATIONS table.
  4. If idle speed requires adjustment, remove plug and rotate idle speed adjusting screw to obtain correct idle speed. See Fig 1 and Fig 2 .
    Fig 1: Adjusting Idle Speed (Prizm)
    G121581Courtesy of GENERAL MOTORS CORP.
    Fig 2: Adjusting Idle Speed (Prizm GSi)
    G91A16790Courtesy of GENERAL MOTORS CORP.
  5. On A/C equipped models, turn A/C on low speed. With A/C operating, idle speed should be within specification. See A/C IDLE SPEED SPECIFICATIONS table.
  6. If idle speed requires adjustment, rotate adjustment screw on air conditioner idle-up Vacuum Switching Valve (VSV) to obtain correct idle speed. Idle-up VSV is located in right rear corner of engine compartment, near end of intake manifold on Prizm or left rear corner of engine compartment, near mass airflow sensor on Prizm GSi.
  7. On all models, turn engine off and remove tachometer. Remove jumper wire from diagnostic connector and install cover on Prizm models.
IDLE SPEED SPECIFICATIONS (1)

Application Idle RPM
Prizm (2)(3) 700
Prizm GSi (2) 800
(1) If specification differs from emission label, use specification listed on emission label.
(2) Specification listed are with transmission in Neutral on M/T models or in Park on A/T models
(3) Specification listed with jumper wire installed between terminals TE1 (Blue/White wire) and E1 (Brown wire) of diagnostic connector in engine compartment, located on left strut tower.
A/C IDLE SPEED SPECIFICATIONS

Application (1) Engine RPM
Prizm & Prizm GSi (2) 900-1000
(1) Specification listed are with transmission in Neutral on M/T models or in Park on A/T models.
(2) Vacuum Switching Valve (VSV) is used for maintaining idle speed during A/C operation.
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