Mazda 6 Workshop Manual page 242

STEP
26 Inspect the fuel injector.
Is the fuel injector normal?
27 Inspect the IDM.
Is the IDM normal?
28 Inspect the timing belt for followings:
• Gear teeth chipping
• Low tension
• Breakage damage or cracks
Is the timing belt normal?
29 Verify the test results.
• If normal, return to the diagnostic index to service any additional symptoms.
• If the malfunction remains, replace the PCM.
End Of Sie
NO.19 EXCESSIVE BLACK SMOKE
19 EXCESSIVE BLACK SMOKE
• Excessive black smoke is observed in exhaust gas.
DESCRIPTION
• Intake-air system clogging or restriction
• Air leakage from Intake-air system
• Incorrect fuel injection timing
• Erratic signal from CKP sensor
• Fuel pressure sensor or related circuit malfunction
• Boost sensor or related circuit malfunction
• IAT sensor No.2 or related circuit malfunction
• Fuel injector malfunction
• Excessive fuel pressure
• Suction control valve malfunction (built-in supply pump)
• Fuel line clogging or restriction
• Fuel pressure limiter malfunction (built-in common rail)
• Low engine compression
• Improper valve timing
• Base engine malfunction
• EGR system malfunction
• EGR valve position sensor malfunction
POSSIBLE
• Variable boost control (VBC) system malfunction
CAUSE
• Vacuum leakage
• Turbocharger malfunction
• Charge air cooler malfunction
• Intake shutter valve malfunction
• Variable swirl control (VSC) system malfunction
• VSC valve malfunction
• IDM or related circuit malfunction
• Exhaust system and/or catalyst converter restriction or clogging
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
• • • • Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death
F2–230
TROUBLESHOOTING
INSPECTION
sparks and flames away from fuel.
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.
RESULTS
Yes Go to the next step.
No Repair or replace if necessary.
Yes Go to the next step.
No Repair or replace if necessary.
Yes Inspect the following:
• ECT sensor
• Boost sensor
• MAF/IAT sensor
• Catalyst converter
If normal, remove and inspect the supply pump and
the common rail.
No If the timing is incorrect, adjust the valve timing.
If the timing belt is not normal, replace timing belt.
ACTION
B6E408018881110