DIAGNOSTIC PROCEDURE
DIAGNOSTIC PROCEDURE
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] .)
CAUTION:
z
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.
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-
3.5]
.)
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-3.5]
.)
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-3.5]
.)
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-
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
Microsoft
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© 2005 Mitchell Repair Information Company, LLC.