No. 7 Slow Return To Idle

7	SLOW RETURN TO IDLE
DESCRIPTION	The engine takes more time than normal to return to idle speed.
POSSIBLE CAUSE	ECT sensor malfunction Thermostat is stuck open Erratic signal from PSP switch Throttle body malfunction Air leakage from intake-air system

DIAGNOSTIC PROCEDURE

STEP	INSPECTION	RESULTS	ACTION
1	Turn the ignition switch to the ON position (Engine off). Retrieve any DTCs. Are there any DTCs displayed?	Yes	Go to the appropriate DTC inspection. (See DTC TABLE ).
1		No	Go to the next step.
2	Monitor the ECT PID using the M-MDS. Start the engine and warm it up to ECT PID is above 90°C {194°F}. Does the ECT PID increasing dull at the thermostat initial opening temperature? Thermostat initial opening temperature: 80-84 °C {176-183°F}	Yes	Inspect characteristic of the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION ).
2		No	Thermostat operation is normal. Go to the next step.
3	Access the PSP PID using the M-MDS. Do the PIDs indicate the correct values under trouble condition?	Yes	Go to the next step.
3		No	inspect and repair or replace power steering pressure switch and the related harnesses. If the malfunction remains, perform the intermittent concern troubleshooting procedure.
4	Is the throttle body free of contamination?	Yes	Inspect for air leakage from the intake-air system components while racing the engine to higher speed.
4	Is the throttle body free of contamination?	No	Clean or replace the throttle body. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION ).
5	Verify test results. If normal, return to diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX ). If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. If vehicle is repaired, troubleshooting completed. If vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM REMOVAL/INSTALLATION ).