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

  1. Turn all lights and accessories off. Connect tachometer to engine. Disconnect and plug vacuum connector at EGR CVSCC valve. Jumper radiator fan connector so fan will run continuously. If equipped, disconnect oxygen system test connector. Remove PCV valve and allow it to draw outside air. Ground carburetor switch. If equipped, disconnect and plug vacuum hose at solenoid kicker.
  2. Start engine and momentarily raise engine speed above 1100 RPM and wait 2 minutes for engine speed to stabilize. Tachometer should indicate same RPM as shown on emission label. If idle speed is okay, proceed to next test. If idle speed is not okay, turn idle speed screw until engine RPM is the same as shown on emission label.
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