Specifications

ON-BOARD DIAGNOSTIC
F109
F
3 VERIFY RELATED PENDING AND STORED
DTCS
• Turn ignition key to OFF, then ON (Engine
OFF).
• Verify pending and /or stored DTCs using WDS
or equivalent.
• Is DTC P0443 also present?
Yes Go to DTC P0443 troubleshooting procedures, then go to
Step 13.
No Go to next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME
DATA
• Is DTC P0133 on FREEZE FRAME DATA?
Yes Go to next step.
No Go to troubleshooting procedures for DTC on FREEZE
FRAME DATA.
(See F67 DTC TABLE.)
5 VERIFY CURRENT INPUT SIGNAL STATUS
• Warm up engine.
• Access O2S11 PID using WDS or equivalent.
• Inspect PID under following accelerator pedal
conditions (in PARK (ATX) or NEUTRAL
(MTX)).
• Is PID reading okay?
 More than 0.55 V when suddenly depress
accelerator pedal (rich condition).
 Less than 0.55 V just after release of
accelerator pedal (lean condition).
Yes Go to step 8.
No Go to next step.
6 INSPECT INSTALLATION OF FRONT HO2S
• Inspect if front HO2S is loosely installed.
• Is sensor installed securely?
Yes Go to next step.
No Retighten sensor, then go to Step 13.
7 INSPECT GAS LEAKAGE FROM EXHAUST
SYSTEM
• Visually check if any gas leakage is found
between exhaust manifold and front HO2S.
• Is there any gas leakage?
Yes Repair or replace any faulty exhaust parts, then go to Step
13.
No Replace sensor, then go to Step 13.
8 INSPECT LONG TERM FUEL TRIM
• Access LONGFT1 PIDs
• Compare it with FREEZE FRAME DATA
recorded at Step 1.
• Is it below FFD value?
Yes Engine is driven under rich condition. Go to next step.
No Engine is driven under lean condition. Go to step 10.
9 INSPECT FUEL LINE PRESSURE (Excessive
fuel line pressure)
• Turn ignition key to OFF.
• Inspect fuel line pressure while engine running.
(See F20 FUEL LINE PRESSURE
INSPECTION.)
• Is fuel line pressure okay?
Yes Go to next step.
No Inspect fuel pump maximum pressure and fuel return pipe
for clogging.
(See F25 FUEL PUMP UNIT INSPECTION.)
• If any problem is found, repair or replace suspected
parts.
• If all items above are okay, replace fuel pump unit.
Then go to Step 13.
10 INSPECT FUEL LINE PRESSURE (Low fuel line
pressure)
• Turn ignition key to OFF.
• Inspect fuel line pressure while engine running.
(See F20 FUEL LINE PRESSURE
INSPECTION.)
• Is fuel line pressure okay?
Yes Go to step 13.
No Go to next step.
11 INSPECT FUEL LINE FROM FUEL PUMP TO
FUEL DELIVERY PIPE
• Visually inspect fuel line for any leakage.
• Is any fuel leakage found?
Yes Replace suspected fuel line, then go to Step 13.
No Inspect fuel filters for following:
• Restriction or clogging at fuel filter (high-pressure side)
• Foreign materials or stain inside fuel filter (low-pressure
side)
Perform following actions according to result.
• If restriction or clogging is found at fuel filter (high-
pressure side), replace fuel filter.
• If foreign material or stain is found inside fuel filter (low-
pressure side), clean of fuel tank and filter.
• If all items above are okay, replace pressure regulator.
Then go to Step 13.
STEP INSPECTION ACTION