DIAGNOSTIC PROCEDURE
NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE (MZI-3.7) DIAGNOSTIC PROCEDURE
material.
STEP
INSPECTION
RESULTS
ACTION
1
Connect the M-MDS to the 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.
No
Inspect the cooling system for cause of
overheating.
2
Connect the M-MDS to the DLC-2.
Access IAT and MAF PIDs.
Monitor each PID.
(See
PCM INSPECTION [MZI-
3.7]
.)
Are PIDs normal?
Yes
Go to the next step.
No
IAT PID:
Inspect IAT sensor
MAF PID:
Inspect MAF sensor
3
Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON
position (engine off).
Are there any DTCs displayed?
Yes
DTC is displayed:
Go to the appropriate DTC inspection.
(See
DTC TABLE [MZI-3.7]
.)
No
No DTC is displayed:
Go to the next step.
4
Is engine compression correct?
Yes
Go to the next step.
No
Inspect for cause.
5
Install fuel pressure gauge between
fuel pipe and fuel distributor.
Start the engine and idle it.
Measure fuel line pressure during
idle.
Is fuel line pressure correct during
idle?
(See
FUEL LINE PRESSURE
INSPECTION [MZI-3.7]
.)
Yes
Inspect the ignition timing.
No
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]
.)
6
Inspect the knock sensor.
Is the knock sensor normal?
Yes
Inspect ignition timing.
No
Replace the knock sensor.
7
z
Verify test results.
{
If normal, return to diagnostic index to service any additional symptoms.
(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
Microsoft
Sunday, November 15, 2009 10:10:05 AM
Page 62
© 2005 Mitchell Repair Information Company, LLC.
