POSSIBLE CAUSE
z
Vacuum leakage
z
Poor fuel quality
z
Erratic signal to ignition coil
z
Engine overheating
z
Throttle body malfunction
z
Spark plug malfunction
z
PCV valve malfunction
z
Improper valve timing due to jumping out of timing chain
z
Improper variable valve timing control operation
z
Restriction in exhaust system
z
Intermittent open or short in fuel pump related circuit
z
Inadequate fuel pressure Fuel pump mechanical malfunction
z
Fuel line restriction or clogging
z
Fuel leakage from fuel injector
z
Fuel injector clogging
z
Erratic signal from accelerator pedal position sensor
z
Erratic signal from TP sensor
z
Intermittent open or short circuit in MAF sensor, Accelerator pedal position
sensor, TP sensor, IAT sensor and VSS
z
ATX malfunction
WARNING:
The following troubleshooting flow chart contains the fuel system
diagnosis and repair procedures. Read the following warnings before
servicing the fuel system:
z
Fuel vapor is hazardous. It can easily ignite, causing serious injury
and damage. Always keep sparks and flames away from fuel.
z
Fuel line spills and leakage are dangerous. Fuel can ignite and
cause 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
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
Microsoft
Sunday, November 15, 2009 9:27:37 AM
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