21NA255

Bulletin No.:
Service Bulletin
Date:
21-NA-255
November, 2021
TECHNICAL
Subject:
Engine Misfire, Malfunction Indicator Lamp (MIL) Illuminated - DTC P0300 Set
Brand:
Model:
Buick
Encore
Chevrolet
GMC
Holden
Model Year:
VIN:
from
to
2021
2022
from
to
Engine:
(1.4L, 1.5L)
Transmission:
LE2
Cruze
2018
2019
LE2
Equinox
2018
2022
LYX
Malibu
2018
2022
Trax
2020
2022
Terrain
2018
2022
LYX
Astra K
2017
2019
LE2
Equinox
2018
2019
LYX
—
—
LFV
LE2
—
Involved Region or Country
North America, Middle East, Israel, Palestine, Argentina, Brazil, Chile, Colombia,
Ecuador, Paraguay, Peru, Uruguay, GM Korea Company, China, Thailand, Australia/New
Zealand, Egypt, Other Africa
Condition
Some customers may comment on one or more of the following conditions:
• MIL illuminated
• Engine misfire
Technicians may find DTC P0300 set in the Engine Control Module (ECM).
Cause
5920461
This condition may be caused by a broken spark plug insulator.
If you encounter a vehicle with an engine misfire or engine misfire related DTC, perform
the following:
Correction
Copyright 2021 General Motors LLC. All Rights Reserved.
⇒ Remove the spark plugs from the engine and inspect for a broken center
insulator by inverting the spark plug. Once the spark plug has been inverted,
you may find the insulator will slide down the center electrode.
Page 2
November, 2021
Bulletin No.: 21-NA-255
Service Procedure
Refer to Gas Engine Ignition Spark Plug Inspection and
Gas Engine Ignition Spark Plug Replacement in SI.
Warranty Information
For vehicles repaired under warranty, use:
Labor
Operation
Description
Labor Time
Gas Engine Ignition Spark
Plug Replacement - Multiple
Use
Published
Labor
Operation
Time
4020061
Version
1
Modified
Released November 09, 2021
Additional SI Keywords: P0301, P0302, P0303, P0304
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
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