Mazda 6 2002 Workshop Manual page 203

STEP
2 VERIFY RELATED SERVICE INFORMATION
AVAILABILITY
• Check for related Service Information
availability.
• Is any related Service Information available?
3 VERIFY RELATED PENDING AND STORED
DTCs
• Turn ignition key to OFF, then ON (Engine
OFF).
• Verify pending and stored DTCs using WDS or
equivalent.
• Is other DTC present?
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME
DATA
• Is DTC P0131 and P0132 on FREEZE FRAME
DATA?
5 VERIFY CURRENT INPUT SIGNAL STATUS - IS
CONCERN INTERMITTENT OR CONSTANT
• Warm-up engine.
• Access O2S11 for P0131 and P0132 PID using
WDS or equivalent.
• Verify PID while racing engine (in PARK (ATX)
or NEUTRAL (MTX)).
• Is PID reading okay?
— More than 0.45 V when suddenly depress
accelerator pedal (rich condition)
— Less than 0.45 V just after release of
accelerator pedal (lean condition)
6 INSPECT LONG TERM FUEL TRIM
• Access LONGFT1 for P0131 and P0132 PID
using WDS or equivalent.
• Compare it with FREEZE FRAME DATA
recorded at Step1.
• Was it decreased?
7 INSPECT FUEL LINE PRESSURE (EXCESSIVE
FUEL LINE PRESSURE)
• Turn ignition key to OFF.
• Inspect fuel line pressure.
(See F–20 FUEL LINE PRESSURE
INSPECTION.)
• Is fuel line pressure okay?
8 INSPECT PURGE SOLENOID VALVE FOR
STUCK OPEN
• Turn ignition key to OFF.
• Disconnect both hoses from purge solenoid
valve.
• Blow air through purge solenoid valve.
• Does air blow through?
9 INSPECT PCV VALVE OPERATION
• Inspect PCV valve operation.
(See F–41 PCV VALVE
• Is PCV valve okay?
10 INSPECT FUEL LINE PRESSURE (LOW FUEL
LINE PRESSURE)
• Turn ignition key to OFF.
• Inspect fuel line pressure.
(See F–20 FUEL LINE PRESSURE
INSPECTION.)
• Is fuel line pressure okay?
11 INSPECT FUEL PUMP MAXIMUM PRESSURE
• Stop engine.
• Turn ignition key to ON (Engine OFF).
• Perform fuel pump maimum pressure test.
(See F–20 FUEL LINE PRESSURE
INSPECTION.)
• Is fuel pump maimum pressure okay?
F–106
ON-BOARD DIAGNOSTIC
INSPECTION
INSPECTION.)
Yes Perform repair or diagnosis according to available Service
Information.
• If vehicle is not repaired, go to net step.
No Go to net step.
Yes Go to appropriate DTC troubleshooting procedures.
No Go to net step.
Yes Go to net step.
No Go to troubleshooting procedures for DTC on FREEZE
FRAME DATA.
Yes Go to net step.
No Replace front HO2S, then go to Step 19.
Yes Engine is driven under rich condition. Go to net step.
No Engine is driven under lean condition. Go to step 9.
Yes Go to net step.
No Inspect following parts and repair or replace if necessary:
• Fuel pump maimum pressure
• Fuel return pipe for clogged
— If all items above are okay, replace pressure
regulator. Then, go to Step 19.
Yes Replace purge solenoid valve.
No Go to Step 13.
Yes Go to net step.
No Replace PCV, then go to Step 19.
Yes Go to step 13.
No Go to net step.
Yes Go to net step.
No Inspect fuel pump circuit for open or poor connection.
• Repair or replace suspected circuit.
• If circuit is okay, replace fuel pump.
Then go to Step 19.
ACTION