Mazda CX-9 Grand Touring 2007 Manual page 876

2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
CAUTION:
DIAGNOSTIC PROCEDURE
DIAGNOSTIC PROCEDURE
STEP INSPECTION
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?
2 Connect the M-MDS to the DLC-2.
Access IAT and MAF PIDs.
Monitor each PID.
(see PCM INSPECTION [MZI-
3.5] .)
Are PIDs normal?
3 Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON
position (engine off).
Are there any DTCs displayed?
4 Is engine compression correct?
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-3.5] .)
2007 Mazda CX-9 Grand Touring
serious injuries or death and damage. Fuel can also irritate skin and
eyes. To prevent this, always complete "BEFORE REPAIR PROCEDURE"
and "AFTER REPAIR PROCEDURE" described in this manual.
(see BEFORE REPAIR PROCEDURE [MZI-3.5] .)
(see AFTER REPAIR PROCEDURE [MZI-3.5] .)
Disconnecting/connecting quick release connector without cleaning it
may cause damage to fuel pipe and quick release connector. Always
clean quick release connector joint area before
disconnecting/connecting, and make sure that it is free of foreign
material.
RESULTS
Yes Go to the next step.
No Inspect the cooling system for cause of
overheating.
Yes Go to the next step.
No IAT PID:
Inspect IAT sensor
MAF PID:
Inspect MAF sensor
Yes DTC is displayed:
Go to the appropriate DTC inspection.
(see DTC TABLE [MZI-3.5] .)
No No DTC is displayed:
Go to the next step.
Yes Go to the next step.
No Inspect for cause.
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-
ACTION