Circuit/System Verification: P0172

WARNING: This page is about a different variant/trim than selected.

NOTE: EVAP purge enablement may cause the FT to be momentarily outside the normal range.

Allow the engine to reach operating temperature. With the engine running, observe the Long Term FT parameter with a scan tool. The reading should be between -20 and 0 percent.

If less than the specified range, inspect for the following:

Vacuum hoses for splits, kinks, and improper connections
The air intake duct for being collapsed or restricted
The air filter for being dirty or restricted
Objects blocking the throttle body
Excessive fuel in the crankcase due to leaking fuel injectors
The EVAP control system for improper operation
Excessive fuel pressure-Refer to Fuel System Diagnosis .
Malfunctioning fuel injectors-Refer to Fuel Injector Diagnosis (J39021 or Tech 2) or Fuel Injector Diagnosis (CH47976) .
Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
The HO2S for improper installation and for electrical wires or connectors that may have contacted the exhaust system
The HO2S signal circuit shorted to voltage
Malfunctioning engine components-Refer to Symptoms - Engine Mechanical .