Mazda Mazda6 Workshop Manual Supplement page 347

NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE
12 LACK/LOSS OF POWER-ACCELERATION CRUISE
• Performance is poor under load (e.g., power down when climbing hills).
DESCRIPTION
• Poor fuel quality
• Air leakage from intake-air system
• Intake-air system restriction or clogging
• Engine overheating
• A/C system improper operation
• Improper operation of A/C cut-off control
• Variable boost control (VBC) system malfunction
• Variable swirl control (VSC) system malfunction
• EGR system malfunction
• Vacuum leakage
• Clutch slippage
• Exhaust system and/or catalyst converter restriction
• Fuel line or clogging or restriction
• Fuel filter clogging or restriction
• Incorrect fuel injection timing
• Erratic signal from CKP sensor
• Erratic signal from CMP sensor
• ECT sensor or related circuit malfunction
• Boost sensor or related circuit malfunction
• Accelerator position sensor or related circuit malfunction
• Idle switch or related circuit malfunction
• MAF/IAT sensor or related circuit malfunction
• IAT sensor No.2 or related circuit malfunction
• Incorrect adjustment accelerator position sensor and/or idle switch
POSSIBLE
• Incorrect idle speed
CAUSE
• Inadequate fuel pressure
• Fuel pressure sensor or related circuit malfunction
• Suction control valve malfunction (built-in supply pump)
• Fuel pressure limiter malfunction (built-in common rail)
• Supply pump malfunction
• Fuel injector malfunction
• Low engine compression
• Improper valve timing
• Cooling fan No.1 or cooling fan No.2 seat are improper
• Turbocharger malfunction
• Charge air cooler malfunction
• Brake system dragging
• Intake shutter valve malfunction
• Guide blade valve malfunction
• IDM or related circuit 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 injury 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.
Diagnostic Procedure
STEP INSPECTION
1 Is idle speed stable?
2 Is engine overheating?
TROUBLESHOOTING
RESULTS
Yes Go to next step.
No Go to symptom troubleshooting "NO.8 ENGINE RUNS
ROUGH/ROLLING IDLE".
Yes Go to symptom troubleshooting "NO.17 COOLING
SYSTEM CONCERNS—OVERHEATING".
No Go to next step.
A6E408018881214
ACTION
F2–195
F2