5
between the fuel pipe and the 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]
.)
No
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 for variable valve timing
control system operation.
(See
ENGINE CONTROL
SYSTEM OPERATION
INSPECTION [MZI-3.7]
.)
Does the variable valve timing
control system function properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part.
7
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace the PCV valve.
8
Visually inspect the exhaust system
part.
Is there any deformed exhaust
system?
Yes
Replace the suspected part.
No
Go to the next step.
9
Inspect for contaminated MAF
sensor.
Is there any contamination?
Yes
Go to the next step.
No
Inspect for cause.
10
Inspect the MAF sensor for
contamination.
Is there any contamination?
Yes
Replace MAF sensor.
No
Go to the next step.
11 Is engine compression correct?
Yes
Inspect the valve timing.
No
Inspect for cause.
12
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
Information and perform repair or diagnosis.
z
If vehicle is repaired, troubleshooting completed.
z
If vehicle is not repaired or additional diagnostic information is not available,
replace the PCM.
(See
PCM REMOVAL/INSTALLATION [MZI-3.7]
.)
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 65
© 2005 Mitchell Repair Information Company, LLC.
