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Home >> Plymouth >> 1987 >> Horizon Standard >> Repair and Diagnosis >> Engine Performance >> System >> EFC System >> DRIVEABILITY Tests >> Test 26 - Engine Idle System >> Checking Fast Idle RPM
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Checking Fast Idle RPM

  1. All lights and accessories should be off, tachometer connected to engine, vacuum connector at EGR CVSCC disconnected and plugged, radiator fan running, PCV valve removed and carburetor switch grounded. Where applicable, oxygen system test connector should be disconnected. Engine should be running at normal operating temperature.
  2. Turn propane valve off. Open throttle and set fast idle adjustment screws on the slowest speed step of the fast idle cam. Fast idle speed should be within specification shown on emission label. If fast idle speed is okay, proceed to next test. If fast idle speed is not okay, adjust to specification.
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