DIAGNOSTIC PROCEDURE
NO.4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK (MZI-3.7)
DIAGNOSTIC PROCEDURE
POSSIBLE
CAUSE
z
Spark plug malfunction
z
Air leakage from intake-air system
z
Erratic signal from CKP sensor
z
Erratic signal from CMP sensor
z
Improper air/fuel mixture ratio control
z
Air cleaner restriction
z
Improper operation of electronic throttle control system
z
PCV valve malfunction
z
Inadequate fuel pressure
z
Purge solenoid valve malfunction
z
MAF sensor contamination
z
Incorrect MAF sensor GND voltage
z
Restriction in exhaust system
z
Pressure regulator malfunction (built-in fuel pump unit)
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 SERVICE
PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this
manual.
(See BEFORE SERVICE PRECAUTION [MZI-3.7] .)
(See AFTER SERVICE PRECAUTION [MZI-3.7] .)
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.
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:10:04 AM
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© 2005 Mitchell Repair Information Company, LLC.
