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Idle Speed (TBI)

  1. Start engine and warm to normal operating temperature. Install spare fuse into diagnosis terminal of fuse box and ensure CHECK ENGINE light indicates Code 12. See Fig 1 .
    Fig 1: Installing Diagnosis Terminal Fuse
    G90A18010Courtesy of SUZUKI OF AMERICA CORP.
  2. Turn engine off and connect Duty Meter (99963-00006) to test connector terminals "A" (Violet wire) and "C" (ground terminal-Black/Green wire). Test connector is located near battery. Turn ignition on and wait 5 seconds. See Figure .
  3. Start engine, run at 2000 RPM for 5 minutes, then return to idle. Using Duty Meter (99963-00006), ensure idle speed and ISC duty percentage are within specification. See IDLE SPEED SPECIFICATIONS (TBI)  table. If idle speed and/or ISC duty percentage require adjustment, remove idle speed adjusting screw protective cap on throttle body. Turn idle speed adjusting screw to adjust idle to specification. See Fig 2 .
    Fig 2: Locating Idle Speed Adjusting Screw
    G90C20786Courtesy of SUZUKI OF AMERICA CORP.
  4. When idle speed and ISC duty percentage are within specification and vehicle is A/C equipped, proceed to step 5). If vehicle is not A/C equipped, reinstall idle speed adjusting screw protective cap to throttle body and remove spare fuse from diagnosis terminal. Remove duty meter from test connector and reinstall cap.
  5. Turn A/C on and set fan switch to LOW position. Check idle speed and ISC duty percentage. See IDLE SPEED SPECIFICATIONS (TBI)  table. If idle speed and/or ISC duty percentage is not within specification, turn A/C VSV adjusting screw to adjust idle to specification. See Fig 3 .
Fig 3: Locating A/C VSV Adjusting Screw
G90D20787Courtesy of SUZUKI OF AMERICA CORP.
IDLE SPEED SPECIFICATIONS (TBI) (1)

Application Idle RPM
With A/C Off (2) 750-850
With A/C On (2)(3) 950-1050
(1) Idle speed specification is with transaxle or transmission in Neutral or Park.
(2) ISC duty percentage should be 50% on Duty Meter (99963-00006).
(3) The A/C idle speed is adjusted by rotating adjusting screw on the A/C Vacuum Switching Valve (VSV). See Fig 3 .
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