Diagnostic Aids

WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.

The 5.3L engine, VIN code Z, may use either 100% pure unleaded fuel or unleaded fuel containing up to 85% ethanol, or E85. Refer to Fuel System Description . This DTC can set if the learned alcohol content is not within 15% of the actual alcohol content in the fuel tank. Refer to Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool and without E85) or Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) .
Fuel contamination, such as water, will effect fuel trim.
A malfunctioning MAF sensor can cause a rich condition and set this DTC. Refer to DTC P0101 (With Throttle Actuator Control) .
Review Failure Records with a scan tool. If an intermittent condition is suspected, refer to Testing for Intermittent Conditions and Poor Connections .