Bulletin No.:

Service Bulletin

Date:

18-NA-291
November, 2020

TECHNICAL
Subject:

Reduced Performance, Reduced Power, Engine Misfire, Malfunction Indicator Lamp
(MIL) Illuminated - DTC P0300 Set After Service or Replacement of Charge Air Cooler

Brand:

Model:

Cadillac
Chevrolet

Model Year:

VIN:

from

to

CTS

2016

2019

Camaro

2017

2021

from

to

—

—

Engine:

Transmission:

6.2L (RPO LT4)

—

Involved Region or Country

North America, Europe, Russia, Middle East, Israel, Argentina, Brazil, Bolivia, Chile,
Colombia, Ecuador, Paraguay, Peru, Uruguay, Japan, GM Korea Company, Cadillac
Korea (South Korea), China, Taiwan, Philippines

Condition

Some customers may comment on one or more of the following conditions while track
driving during high ambient temperatures:
• Reduced Performance
• Reduced Power
• Engine Misfire
• MIL Illuminated
During diagnosis, a technician may find DTC P0300 (Engine Misfire Detected) set or
stored in the Engine Control Module (ECM).

Cause

This condition may be caused by the supercharger’s charge air cooler system not being
properly evacuated and filled after service or replacement of the charge air cooler.

Correction

If you encounter a vehicle with the above concern, refer to the Service Procedure below.

Service Procedure
Important: This procedure must be performed when
the intercooler system is cool.
Special Tools
Any time that the supercharger’s cooling system is
replaced, removed or separated from the engine, it
must be properly drained and filled using the following
special tools:
• GE-26568 Coolant and Battery Fluid Tester
• GE-47716 Vac-N-Fill Coolant Refill Tool
• GE-52079 Tool, Coolant System Fill
• GE-52079-10 Adapter, Coolant System Fill Tool

Open Fill Port Installation
Important: It may be necessary to replace the system
fill port in order for service tool GE-52079 and adapter
52079-10 can be used to bleed the charge air cooler
system. The new fill port will remain installed after the
bleed procedure is completed.
1. Evacuate .5 qt (.5 L) of coolant from the system.
2. Place a rag under the fill port to catch any coolant
that may spill when the system is opened.

Copyright 2020 General Motors LLC. All Rights Reserved.

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3. Remove the charge air cooler coolant hose
retainer (1).
4. Loosen the Schrader valve port hose clamp and
position away from port.

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November, 2020

Bulletin No.: 18-NA-291

5. Separate the Schrader valve port from the
hose (2).

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6. Assemble the new fill port (3) with cap (2) and 90
degree elbow (4).
7. Install the fill port into the charge air cooler coolant
hose and secure the hose clamp (5).
8. Install the fill port to the engine coolant
manifold (1).

Vac-N-Fill Procedure
Important: To prevent boiling of the coolant/water
mixture in the vehicles cooling system, do not apply
vacuum to a cooling system above 49°C (120°F). The
tool will not operate properly when the coolant is
boiling.
Note: The system will be properly bled when the fluid
appears clear in the reservoir.
1. Install a battery tender/charger.

4913613

2. Add .5 qt (.5 L) of coolant to the system through
service tool GE-52079.
3. Attach the MDI to vehicle.
Note: It is best for the hoses on GE-52079 Tool,
Coolant System Fill to be as straight and vertical as
possible for adequate flow. The GE-52079 Tool,
Coolant System Fill reservoir should be as high as
possible for the hoses to be straight. Zip ties can be
used to fasten the chain links together in order to
shorten the support chain.

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November, 2020

Page 3

5142033

4. Attach GE-52079 Tool, Coolant System Fill lines
(2) to GE-52079-10 Adapter, Coolant System Fill
Tool (3).
Important: When hanging the tank, be sure to protect
the hood surface so the chain/hook does not damage
the hood surface.
5. Utilizing the support chain (1), affix the GE-52079
tank to the hood.

6. Insert the other end of the GE-52079-10 adapter
(2) into the fill port tee.
7. Ensure the arrow (3) on the GE-52079-10 adapter
is parallel with the charge air cooler coolant hose
pointing away from the supercharger inlet.

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8. Attach the vacuum gauge lower port (3) to top port
of the GE-52079 tank.
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Bulletin No.: 18-NA-291

9. Attach the fill hose (1) to the barb fitting (2) on the
vacuum gauge assembly ensuring that the valve is
closed.

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14. Attach the venturi assembly (1) to the vacuum
tank (2).
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Note: Use a 50/50 mixture of DEX-COOL antifreeze
and clean, drinkable water. Always use more coolant
than necessary. This will eliminate air from being drawn
into the cooling system.
10. Using GE-26568 Coolant and Battery Tester, check
the concentration of the coolant/water mixture.
⇒ Prior to installing the vacuum tank onto the
graduated reservoir, ensure that the drain valve
located on the bottom of the tank is closed.
11. Pour the coolant mixture into the graduated
reservoir (1).
12. Place the fill hose from the vacuum gauge, into the
graduated reservoir.
Note: Prior to installing the vacuum tank onto the
graduated reservoir, ensure that the drain valve located
on the bottom of the tank is closed.
13. Install the vacuum tank (2) on the graduated
reservoir with the fill hose routed through the
cut-out area (3) in the vacuum tank.

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15. Attach a shop air hose to the venturi assembly (1).
16. Ensure the valve (2) on the venturi assembly is
closed.

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November, 2020

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17. Attach the vacuum hose (1) to the vacuum gauge
assembly (2) and the vacuum tank (3).

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18. Open the valve (1) on the venturi assembly (2).
⇒ The vacuum gauge will begin to rise and a
hissing noise will be present.

19. Continue to draw vacuum until the needle stops
rising (1). This should be 610-660 mm Hg (24-26
in Hg).
⇒ Cooling hoses may start to collapse. This is
normal due to vacuum draw.
20. To aid in the fill process, position the graduated
reservoir above the coolant fill port.

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Bulletin No.: 18-NA-291

25. Close the valve on the venturi assembly.
26. Detach the vacuum gauge assembly from
GE-47716 Vac-N-Fill Coolant Refill Tool from
GE-52079 Tool, Coolant System Fill.
27. Detach the vacuum hose from the vacuum gauge
assembly.
28. Open the drain valve located on the bottom of the
tank to drain coolant from the vacuum tank into a
suitable container for disposal.

De-Aerating Procedure
Note: The charge air cooler coolant pump will shut off
if it sucks in air. If this occurs, the system must be
drawn into a vacuum to add more coolant. This is a
much quicker way to fill the air pockets as opposed to
just adding coolant from the top of the GE-52079 Tool,
Coolant System Fill reservoir. If the system is not drawn
into a vacuum after the charge air cooler coolant pump
shuts off, this procedure will only take longer if coolant
is just poured in from the top.
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21. Slowly open the valve (1) on the vacuum gauge
assembly (2).
⇒ When the coolant reaches the top of the fill
hose, close the valve. This will eliminate air
from the fill hose.
22. Close the valve on the venturi assembly:
• If there is a suspected leak in the cooling
system, allow the system to stabilize under
vacuum and monitor for vacuum loss.
• If vacuum loss is observed, refer to Loss of
Coolant in SI.
23. Open the valve on the vacuum gauge assembly.
The vacuum gauge will drop as coolant is drawn
into the system.

3242386

24. Once the vacuum gauge (1) reaches zero, close
the valve on the vacuum gauge assembly and
repeat steps 10-16 at least two more times.

1. Unscrew the fill cap on top of the GE-52079 Tool,
Coolant System Fill, to allow the system to vent.
⇒ Do not remove the cap completely, unscrew
approximately 2-3 rotations.
2. Connect a scan tool to the vehicle.
3. Connect a battery charger to keep the battery
charged during the de-aerating procedure.
4. Turn the ignition to the ON position, with the
engine OFF.
5. Using the scan tool, navigate to special functions
in the Engine Cooling section and command the
charge air cooler coolant pump on.
5.1. Allow the charge air cooler coolant pump to
run continuously.
5.2. The coolant will be opaque in the GE-52079
reservoir to begin with.
5.3. The coolant level will gradually decrease in
the GE-52079 reservoir as the system
de-aerates.
5.4. The level in GE-52079 reservoir should
always be more than half full.
⇒ Too low of a coolant level will cause turbulence,
which will make it difficult to remove the air from
the system.
6. Observe the coolant state of flow:
• If coolant flow is noticed to have stopped, the
charge air cooler coolant pump has shut off.
⇒ This will be caused by the charge air cooler coolant
pump sucking in air.
• If this occurs, repeat the Vac-N-Fill procedure to
pull the system into a vacuum to remove air,
followed by adding more coolant as needed.
7. Once the level is stabilized just over the halfway
point, command the charge air cooler coolant
pump back on and continue.
8. Continue to observe the coolant in the GE-52079
reservoir:
⇒ Once the coolant is flowing clear with absolutely
no air bubbles to be seen, the procedure is
complete.

Bulletin No.: 18-NA-291

November, 2020

Page 7

9. Using the scan tool, command the charge air
cooler coolant pump off.
10. Disconnect the scan tool from the vehicle.

Parts Information
Causal
Part

Description

Part
Number

Qty

N/A

HOSE, CHRG
AIR CLR COOL

84344455

1

N/A

CONNECTOR,
CHRG AIR CLR
COOL HOSE

84344461

1

Warranty Information
For vehicles repaired under the Bumper-to-Bumper
coverage (Canada Base Warranty coverage), use the
following labor operation. Reference the Applicable
Warranties section of Investigate Vehicle History (IVH)
for coverage information.
Labor
Operation

Description

Labor Time

4086558*

Vac-N-Fill Procedure

0.7 hr

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

Version

3

Modified

Released September 25, 2018
December 05, 2018 – Updated the CTS Model Year and added Parts Information section.
October 29, 2020 – Added the 2020-2021 Model Years to Camaro, updated the Involved
Region or Country section and clarified the Cause section.

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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