Mazda CX-9 Grand Touring 2009 Manual page 1353

DIAGNOSTIC PROCEDURE
NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE (MZI-3.7) DIAGNOSTIC PROCEDURE
STEP INSPECTION
Connect the M-MDS to the DLC-2.
Access ECT PID.
1 Verify ECT PID is less than 116°C
{241°F} during driving.
Is ECT PID less than specification?
Connect the M-MDS to the DLC-2.
Access IAT and MAF PIDs.
Monitor each PID.
2
(See PCM INSPECTION [MZI-
3.7] .)
Are PIDs normal?
Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON
3
position (engine off).
Are there any DTCs displayed?
4 Is engine compression correct?
Install fuel pressure gauge between
fuel pipe and fuel distributor.
Start the engine and idle it.
Measure fuel line pressure during
5 idle.
Is fuel line pressure correct during
idle?
(See FUEL LINE PRESSURE
INSPECTION [MZI-3.7] .)
Inspect the knock sensor.
6
Is the knock sensor normal?
Verify test results.
If normal, return to diagnostic index to service any additional symptoms.
7
(See SYMPTOM DIAGNOSTIC INDEX [MZI-3.7].)
If malfunction remains, inspect related Service Bulletins and/or On-line Repair
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
material.
RESULTS
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
ACTION
Go to the next step.
Inspect the cooling system for cause of
overheating.
Go to the next step.
IAT PID:
Inspect IAT sensor
MAF PID:
Inspect MAF sensor
DTC is displayed:
Go to the appropriate DTC inspection.
(See DTC TABLE [MZI-3.7] .)
No DTC is displayed:
Go to the next step.
Go to the next step.
Inspect for cause.
Inspect the ignition timing.
Low:
Inspect the fuel pump relay and fuel pump circuit.
Inspect the fuel line for clogging.
If there is no malfunction, replace the fuel pump
unit.
(See FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-3.7] .)
High:
Replace the fuel pump unit.
(See FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-3.7] .)
Inspect ignition timing.
Replace the knock sensor.