Bulletin No.: 16-NA-383

Service Bulletin

Date: June, 2024

TECHNICAL
Subject:

Information on Rough Idle, Crank No Start, Extended Crank or Misfire Due
to Excessive Carbon on Top of Valves or Sticking Valves, Malfunction
Indicator Light (MIL) Illuminated - DTC P0300, P0301, P0302, P0303,
P0304, P0305, P0306, P0307, P0308 Set

This Service Bulletin replaces PIP5029H. Please discard all versions of PIP5029.

Brand:

Buick
Cadillac
Chevrolet
GMC

Model:

GM Passenger Cars and
Light/Medium
Duty Trucks
(including
LCF MD)

Involved Region or Country

Model Year:

VIN:

from

to

from

to

2000

2025

—

—

Engine:

Transmission:

Gasoline
Engines Only

—

North America
Some customers may comment on the following conditions:
• Rough idle
• Crank no start
• Extended crank
• Engine misfire
The technician may find one or more of the following DTCs set:
• P0300
• P0301

Condition

• P0302
• P0303
• P0304
• P0305
• P0306
• P0307
• P0308
SI diagnosis may or may not isolate the cause of the misfire depending on whether the
intake/exhaust valves are sticking at the time of the diagnosis.

Cause

Copyright 2024 General Motors. All Rights Reserved.

This condition may be caused by major carbon build-up on the intake and/or exhaust
valves due to fuel contamination or incomplete burning of the fuel as shown below, so the
misfires should not have appeared until accumulating at least 8,000 km (5,000 mi) or
more.

Page 2

June, 2024

Important: Service agents must comply with all
International, Federal, State, Provincial, and/or
Local laws applicable to the activities it performs
under this bulletin, including but not limited to
handling, deploying, preparing, classifying,
packaging, marking, labeling, and shipping
dangerous goods. In the event of a conflict
between the procedures set forth in this bulletin
and the laws that apply to your dealership, you
must follow those applicable laws.
Note: Fuel oxidation and volatility concerns can often
cause these issues as well, however they cannot
generally be checked in service. Trying a different, high
quality Top Tier fuel and regular oil changes is

Bulletin No.: 16-NA-383

sometimes the best diagnostic. Additional gasoline
retailers are added to the TOP TIER list when their
gasoline meet the TOP TIER Detergent Gasoline
Standards. For the most up to date list of fuel
marketers that offer TOP TIER Detergent Gasoline,
refer to this website: www.toptiergas.com.

Information
Important: A new reformulated Top Engine Cleaner
has been released by CCA Parts and is recommended
and approved to use in the GM vehicle line.
The graphics below may show typical carbon build-up
during engine disassembly and inspection of the
cylinder heads:

2836273

2857954

2836275

2857955

Bulletin No.: 16-NA-383

June, 2024

Page 3

2857957

When the engine is cold, the compression on multiple
cylinders may be at 0 kPa (0 psi).
The engine also may pop through the intake or exhaust
while cranking and the spark plugs may be fuel-fouled
when inspected.
Some engines may also experience valve damage or
cam followers that are out of position as a result of this.
If this concern is encountered, perform SI diagnosis. If
the SI diagnosis leads to a compression loss due to a
valve sealing concern and/or eliminates everything else
external to the engine, the following information may
help:

2857956

• If there is no sign of valve damage or cam
followers that are out of place, perform the
following procedure to free up sticking valves and
to remove carbon from the valves and pistons.
• If valve damage is present or if there are cam
followers that are out of place, perform engine
mechanical repairs as necessary to correct the
concern and then perform the procedure below to
prevent the concern from returning.
• Perform an upper engine and valve cleaning
procedure.
• Below are examples of valves that have gone
through a Top Engine cleaning procedure.

Page 4

June, 2024
Before Cleanup

Bulletin No.: 16-NA-383
After Cleanup

3979074

3979169

4791643

4791651

Bulletin No.: 16-NA-383

June, 2024

Page 5

Before Cleanup

After Cleanup

4791647

4791652

4791649

4791655

Video Training (U.S. Dealers)
There is also a related training video on this subject
that was included in the January 2013 Emerging Issues
Video that technicians should consider viewing.
Because the training video does not mention this,
please note that it is acceptable to use equivalent tools
and the engine oil and filter should also be replaced to
complete the repairs. The training video is available at
the GM Center of Learning Website and can be viewed
by following this path:
⇒

Go to www.centerlearning.com

⇒

Enter Training ID

⇒

Click Resources

⇒

Click Service Know How / Tech Assist

⇒

Click Emerging Issues

⇒

Click 10213.01D - January 2013 Emerging Issues
(VOD)

⇒

Click the Topics Tab on Upper Right
Description

Course Name and Number

Decarbonizing Valves in SIDI
Engines

#10213.01D January 2013
Emerging Issues (VOD)

Top Tier Detergent Gasoline
Featuring: Bulletin
05-06-04-022

#10214.10D October 2014
Emerging Issues

Page 6

June, 2024

Service Procedure
Warning: Please follow all safety instructions noted
on the bottle and service tool. Ensure safety
Fuel Injector Cleaner Kit J-35800-A

glasses and gloves are being worn during the
procedure.

Cleaner Nozzle EN-35800-20

4630850

Important: Extreme care must be taken not to
hydro-lock the engine when inducing the cleaner,
especially if it is induced without Fuel Injector
Cleaner Kit J-35800-A or equivalent. If too much
cleaner is induced at too low of an RPM, or if you
force the engine to stall by inducing too much
cleaner at once, the engine may hydro-lock and
bend a connecting rod(s).
1. Fill Cleaner Kit J-35800-A with Air Intake,
Combustion Chamber Cleaner, approximately 650
ml (22 oz-2 cans), and close the cap of the tool
tightly. Set the air pressure to 260 kPa (40 psi) at
the service tool.
2. Using GDS 2 or a Scan Tool, command engine idle
to 2000 rpm to prevent the engine from stalling.
Typically 2,000 rpm will be sufficient.
Note: Two applications of the Top Engine Cleaner may
be necessary to perform a total cleanup depending on
the condition of the combustion chamber.
3. In a well-ventilated area with the engine at
operating temperature, slowly/carefully induce the
Top Engine Cleaner into the engine, which should
take approximately 3 minutes.
⇒

Bulletin No.: 16-NA-383

For best results, it is suggested to induce the
cleaner through the throttle body with Fuel
Injector Cleaner Kit J-35800-A or equivalent
and NEW Cleaner Nozzle EN-35800-20, which
has been developed to help atomize the
cleaner.

4630851

4. After the entire contents of Air Intake, Combustion
Chamber Cleaner has been induced, continue to
run the engine for 2 minutes at idle.
5. Change the engine oil and filter, and advise the
customer to only use one of the Top Tier Gasoline
locations listed at http://www.toptiergas.com and/
or in the latest version of Corporate Bulletin
Number 05-06-04-022 to minimize future deposits.
It can also be recommended to add a bottle of
ACDelco Fuel System Cleaner 44K at every oil
change as mentioned in the latest version of
Corporate Bulletin Number 04-06-04-051.
6. Test drive the vehicle, using only light acceleration, and clear any DTCs if necessary.
Important: GM does not recommend the use of any
aftermarket top engine cleaning product. Some
products may cause harmful effects to components
or seals and may void the terms of the vehicle
warranty. Use only the GM products listed below,
which have been tested and approved.

Bulletin No.: 16-NA-383

June, 2024
Warranty Information

Parts Information
Description
ACDelco Fuel System
Cleaner 44K (Gas Tank
Additive)

Page 7

Part Number

Qty

19435370
(U.S. and
Canada)

1

19368261
(Mexico)

ACDelco Air Intake, Valve
and Combustion Chamber
Cleaner and ACDelco Fuel
System Cleaner 44K (Top
Engine Cleaning Kit)

19435372
(U.S. and
Canada)

Oil Filter, Engine

Refer to EPC

1

Oil, Engine

Refer to EPC

5 qt

1

19369716
(Mexico)

For vehicles repaired under the Emission coverage,
use the following labor operation. Reference the Applicable Warranties section of Investigate Vehicle History
(IVH) for coverage information.
Labor Operation

Description

Labor Time

4080148*

Decarbon Engine Using
Upper Engine Cleaner

0.5 hr

Add

Change Engine Oil and Filter

0.3 hr

*This is a unique Labor Operation for bulletin use only.

Version

7

Modified

Revised May 21, 2019 – Added the 2019 Model Year, updated the Video Training section
to remove Canada and updated step 6 of the Service Procedure.
Revised January 02, 2020 – Added the 2020 Model Year and part numbers for Mexico
parts.
Revised May 08, 2020 – Added information to the Video Training (U.S. Dealers) section
and corrected Part Number to 19369716 for Fuel System Treatment Plus - Gasoline
(Mexico).
Revised June 15, 2021 – Added the 2021-2022 Model Years.
Revised March 13, 2024 – Added the 2023-2024 Model Years and the first Important
statement.
Revised June 27, 2024 – Added the 2025 Model Year, replaced ACDelco Top Engine
Cleaner and Fuel System Treatment Plus information with ACDelco Fuel System Cleaner
44K, and removed the link to PIP5029 under Video Training (U.S. Dealers).

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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