Service VME - Fuel System Lean DTCs P0101 P0171 P0174 - keywords air filter LH6 LM4

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Replacement air filter causes driveability codes.

General Motors has become aware of a condition where a replacement air filter can cause certain driveability codes.

When diagnosing 2004 and 2005 Trailblazers, Envoys and Rainiers that are equipped with a V8 engine and exhibit LEAN CODES P0171, P0174 AND MAF CODE P0101 technicians should determine if the air filter has recently been replaced.

Certain air filters, including some supplied through A/C Delco as part number 19114119, can cause LEAN CODES P0171, P0174 AND MAF CODE P0101 in V8 Equipped Trailblazers, Envoys and Rainiers. These A/C Delco filters, P/N 19114119, can be identified by the black color rubberized end pieces on the filter.

Air filters from GMSPO which do not cause lean codes for these applications can be identified by their colors and part numbers as well. Orange colored rubberized end pieces, which some people see as pink or peach color, as well as light Blue colored end pieces are sold through GMSPO as part number 15036141 and are not known to cause the lean driveability codes previously described.

Although the AC Delco part numbers have other usage and apparently perform without incident in other applications, if a lean driveability code P0171, P0174 AND MAF CODE P0101 is encountered in a V8 equipped Trailblazer, Envoy and Rainier, confirm the vehicle has and orange or blue color air filter rubber P/N 15036141 before proceeding with the diagnosis.

This is Jay Dankovich from Brand Quality.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.