Diagnostic procedure

WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

NO. 13 KNOCKING/PINGING - ACCELERATION/CRUISE DIAGNOSTIC PROCEDURE

STEP	INSPECTION	RESULTS	ACTION
1	Connect WDS or equivalent to DLC-2. Access ECT PID. Verify ECT PID is less than 116°C {241°F} during driving. Is ECT PID less than specification?	Yes	Go to the next step.
1		No	Inspect cooling system for cause of overheating.
2	Connect WDS or equivalent to DLC-2. Access IAT and MAF PIDs. Monitor each PID. (See PCM INSPECTION .) Are PIDs normal?	Yes	Go to the next step.
2		No	IAT PID: Inspect IAT sensor MAF PID: Inspect MAF sensor
3	Connect WDS or equivalent to DLC-2. Turn key to ON (engine off). Are there any DTCs displayed?	Yes	DTC is displayed: Go to .
3		No	No DTC is displayed: Go to the next step.
4	Is engine compression correct	Yes	Go to the next step.
4	Is engine compression correct	No	Inspect for cause.
5	Install fuel pressure gauge between fuel pipe and fuel distributor. Start engine and idle it. Measure fuel line pressure during idle. Is fuel line pressure correct during idle? (See FUEL LINE PRESSURE INSPECTION .)	Yes	Inspect ignition timing.
5		No	Zero or low: Inspect fuel pump relay and fuel pump circuit. Inspect for clogged fuel line. If okay, replace fuel pump unit. High: Replace fuel pump unit.
6	Inspect knock sensor. Is knock sensor normal?	Yes	Inspect ignition timing.
6	Inspect knock sensor. Is knock sensor normal?	No	Replace knock sensor.
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, reprogram PCM if later calibration is available. Retest.