Mazda 6 2002, Workshop Manual

Page: 321 / 1248

TROUBLESHOOTING
F–191
F
NO.5 ENGINE STALLS-AFTER START/AT IDLE
A6E398018881W07
Diagnostic procedure
5 ENGINE STALLS—AFTER START/AT IDLE
DESCRIPTION
•
Engine stops unexpectedly.
POSSIBLE CAUSE
•
A/C system operation is improper
•
Air leakage from intake-air system parts
•
Purge solenoid valve malfunction
•
Improper operation of IAC valve
•
EGR valve malfunction
•
No signal from CKP sensor due to sensor, related wire or wrong installation
•
Vacuum leakage
•
Engine overheating
•
Low engine compression
•
Spark leakage from high-tension leads
•
Poor fuel quality
•
PCV valve malfunction
•
Air cleaner restriction
•
Restriction in exhaust system
•
Electrical connector disconnection
•
Open or short circuit in fuel pump body and related harness
•
No battery power supply to PCM or poor GND
•
Inadequate fuel pressure
•
Fuel pump body mechanical malfunction
•
Fuel leakage from fuel injector
•
Fuel injector clogging
•
Ignition coil malfunction
•
Improper air/fuel mixture ratio control
•
Improper valve timing
•
Improper operation variable valve timing control system (L3-VE)
•
Immobilizer system (PATS) and/or circuit malfunction (if equipped)
•
Pressure regulator malfunction
Warning
The following troubleshooting flow chart contains the fuel system diagnosis and repair
procedures. Read the following warnings before performing the fuel system services:
•
Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always
keep sparks and flames away from fuel.
•
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
F–17 BEFORE REPAIR PROCEDURE .)
(See F–17 AFTER REPAIR PROCEDURE .)
Caution
•
Disconnecting/connecting quick release connector without cleaning it may possibly 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 Note
•
The following test should be performed for
vehicles with immobilizer system. Go to
Step 10 for vehicles without immobilizer
system.
Connect WDS or equivalent to DLC-2.
Do following conditions appear?
•
Engine is not completely started.
•
DTC B1681 is displayed.
Yes Both conditions appear:
Go to Step 3.
No Either or other condition appears:
Go to next step.
2 Does engine stall after approx. 2 seconds since
engine is started?
Yes Go to next step.
No Immobilizer systemis okay.
Go to Step 10.
3 Is coil connector securely connected to coil? Yes Go to next step.
No Connect coil connector securely.
Return to Step 2.