Diagnostic procedure

WARNING: This page is about a different car, the 2005 Mazda MPV. However, it is still accessible from the selected car via links, so may be relevant.

LOW IDLE/STALLS DURING DECELERATION - DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	Does engine idle rough?	Yes	Go to symptom troubleshooting in NO.8 ENGINE RUNS ROUGH/ROLLING IDLE .
1	Does engine idle rough?	No	Go to next step.
2	Verify following: Proper routing and no damage of vacuum lines IAC valve properly connected No air leakage from intake-air system Are all items okay?	Yes	Go to next step.
2		No	Service as necessary. Repeat Step 2.
3	Connect WDS or equivalent to DLC-2. Turn ignition key to ON (Engine OFF). Retrieve any DTC. Is "PASSED" displayed?	Yes	No DTC is displayed: Go to next step.
3		No	DTC is displayed: Go to appropriate DTC test.
4	Does idle speed drop or stall when disconnecting IAC valve?	Yes	Go to next step.
4	Does idle speed drop or stall when disconnecting IAC valve?	No	Inspect following: Circuit from IAC valve to PCM connector terminal 87 or 88 for open and short IAC valve for sticking If okay, go to next step.
5	Disconnect vacuum hose between purge solenoid valve and intake manifold from purge solenoid valve side. Plug opening end of vacuum hose. Drive vehicle. Does engine condition improve?	Yes	Inspect EVAP control system.
5		No	Go to next step.
6	Connect WDS or equivalent to DLC-2. Access TP, MAF and VSS PIDs. Monitor each PID while driving vehicle. (See PCM INSPECTION USING THE SST (WDS OR EQUIVALENT) ) Are PIDs okay?	Yes	Intermittent concern exists. (See INTERMITTENT CONCERN TROUBLESHOOTING .)
6		No	TP PID: Inspect TP sensor. MAF PID: Inspect MAF sensor. VSS PID: Inspect VSS.
7	Verify test results. If okay, return to diagnostic index to service any additional symptoms. 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 or reprogram PCM.