POSSIBLE CAUSE
z
Purge solenoid valve malfunction
z
Improper operation of electronic throttle control system
z
Idle learning of electronic throttle control system is not completed
z
Erratic or no signal from CMP sensor
z
Low engine compression
z
Improper valve timing
z
Improper variable valve timing control system operation
z
Erratic signal from CKP sensor
z
Improper air / fuel mixture ratio control operation (abnormal signal form
MAF sensor or HO2S)
z
Open or short circuit in PCM GND circuit
z
Poor fuel quality
z
PCV valve malfunction
z
Air cleaner restriction
z
Restriction in exhaust system
z
Disconnected electrical connectors
z
Inadequate fuel pressure
z
Fuel pump body mechanical malfunction
z
Improper load signal input
z
Fuel line restriction or clogging
z
Improper fuel injection control operation
z
Fuel leakage from fuel injector
z
Fuel injector clogging
z
Engine overheating
z
Vacuum leakage Pressure regulator malfunction (built-in fuel pump unit)
WARNING:
The following troubleshooting flow chart contains fuel system diagnosis
and repair procedures. Read 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] .)
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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© 2005 Mitchell Repair Information Company, LLC.