Unique Idle Concern

DETECTION CONDITION AND POSSIBLE CAUSE

4	UNIQUE IDLE CONCERN
DESCRIPTION	Slow return to idle

UNIQUE IDLE CONCERN INSPECTION

STEP	INSPECTION		ACTION
1	PRELIMINARY CHECKS Perform the following preliminary checks: Vacuum leaks. Throttle linkage. Intake air system. Throttle body. Are all the checks OK?	Yes	Go to step 2.
1		No	Service as necessary. Verify symptom no longer exists.
2	PERFORM PCM QUICK TEST Are any DTCs displayed during Continuous Memory or Key ON, Engine OFF (KOEO) Self Tests?	Yes	Check for cause, See DIAGNOSTIC TROUBLE CODE NUMBERS .
2		No	Go to step 3.
3	CHECK PCV SYSTEM Remove PCV valve and shake it. Does PCV valve rattle?	Yes	Install PCV valve. Go to step 4.
3		No	Replace PCV valve,
4	CHECK PCV SYSTEM Start engine and bring to normal operating temperature. Disconnect crankcase ventilation hose from throttle body. Place a stiff piece of paper over the hose. Wait one minute. Does vacuum hold paper in place?	Yes	Go to step 5.
4		No	Disconnect evaporative hose. Place a stiff piece of paper over the hose. Wait one minute. Does vacuum hold paper in place? If yes, go to step 9. See EVAPORATIVE EMISSION (EVAP) SYSTEM MALFUNCTION . If no, check for vacuum leaks, obstructions in the PCV system, oil cap, PCV valve, rocker cover bolt torque/gasket leak. Service as required.
5	Verify test results. If OK, See DIAGNOSTIC INDEX to service any additional symptoms