GM Reduced engine power message

What a GM reduced engine power message means

GM has issued a service bulletin #22-NA-008 to address a GM reduced engine power message on the vehicles listed below. You may also find the following trouble codes U060F,U1346, P0101, P0102, P1101 AND/OR P14B6 on the vehicles listed below

Code Definitions:

P0101 Code – Mass or Volume Air Flow Circuit Range/Performance Problem
P0102 Code – Mass or Volume Air Flow Circuit Low Input
P1101 Code – Mass Air Flow Sensor Out of Self-Test Range
P14B6 Code – Mass Air Flow Sensor Signal Message Counter Incorrect
U1345 Code – Engine Control Module LIN Bus 1

Vehicles covered by GM #22-NA-008 service bulletin

2020-2022 Buick Encore GX
2021-2022 Chevrolet Trailblaer

Cause of the GM reduced engine power and trouble

The location of the broken wire

GM has determined that the problem may be caused by a broken wire in the wiring harness for the multifunction sensor, circuit 492. A zip tie installed at the factory was pulled too tight, causing the wire to break when the harness flexes.

Fix for the GM reduced engine power message and associated and trouble codes

GM recommends inspecting the 2nd retainer back from the MAF sensor while the engine is running. The wire is most likely broken at or near the zip tie and malfunctions during acceleration. Wiggle or pull on the harness at this point to identify the break in the wire.

Repair the broken wire using a the replacement pigtails listed below and using waterproof connectors. Pay attention to the distance from the fixed clip mounted to the charge air cooler inlet hose to the fixed clip mounted on the air cleaner housing. The distance must be 3.4” to allow for proper flex during acceleration.

Pigtail connector kit

85518225 pigtail kit to fix a GM reduced engine power message

85519071 (LIH) $32.39 from this Chevrolet Dealer

85518225 (L3T) $39.30 from this GM dealer

A service bulletin is not a recall and the fixes shown are not usually free

A service bulletin is issued by a vehicle manufacturer to notify dealers and vehicle owners of a potential issue that may exist in some vehicles. Service bulletins provide recommended actions to address the issue, such as inspections, repairs, or part replacements. Compliance with service bulletins is not mandatory.

An auto recall is an official notice issued when a manufacturer has determined that a vehicle component is defective and poses a safety concern. Recalls are regulated by the National Highway Traffic Safety Administration (NHTSA). When a safety-related defect is identified, the manufacturer must notify NHTSA and vehicle owners. Recalls require the free repair, replacement, or refund of the defective part by authorized dealers. Vehicle owners are legally obligated to comply with recall notices.

While service bulletins may indicate potential problems, recalls denote actual safety hazards confirmed by the manufacturer and NHTSA. Service bulletins provide guidelines for repairs, but recalls necessitate the correction of the defect. Both aim to prevent issues and ensure vehicle safety, but recalls carry more stringent requirements and compliance is mandated by law.
©, 2023 Rick Muscoplat