6E1–119
X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
Trouble Code P0131 may be set. Refer to Fuel System
Diagnosis.
D
Lean injector(s) – Perform ”Injector Balance Test.”
D
Vacuum leaks – Check for disconnected or damaged
vacuum hoses and for vacuum leaks at the intake
manifold, throttle body, EGR system, and PCV system.
D
Exhaust leaks – An exhaust leak may cause outside air
to be pulled into the exhaust gas stream past the
HO2S, causing the system to appear lean. Check for
exhaust leaks that may cause a false lean condition to
be indicated.
D
Fuel contamination – Water, even in small amounts,
can be delivered to the fuel injectors. The water can
cause a lean exhaust to be indicated. Excessive
alcohol in the fuel can also cause this condition. For the
procedure to check for fuel contamination, Refer to
Fuel System Diagnosis.
If none of the above conditions are present, replace the
affected HO2S.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
3. Diagnostic Trouble Code P0131 failing during
operation may indicate a condition described in the
”Diagnostic Aids” above. If the Diagnostic Trouble
Code P0131 test passes while the Failure Records
conditions are being duplicated, an intermittent
condition is indicated.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the Diagnostic Trouble Code to
be set occurs. This may assist in diagnosing the
condition.