service CHEVROLET IMPALA 2016 10.G Bifuel Manual

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . 2
Instruments and Controls . . . . . . . . 3
Driving and Operating . . . . . . . . . . . 7
Vehicle Care . . . . . . . . . . . . . . . . . . . . 16
Service and Maintenance . . . . . . . 21
Technical Data . . . . . . . . . . . . . . . . . 25
Index . . . . . . . . . . . . . . . . . . . . . 27

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
2 Introduction
Introduction
The names, logos, emblems,
slogans, vehicle model names, and
vehicle body designs appearing in
this manual including, but not limited
to, GM, the GM logo, CHEVROLET,
the CHEVROLET Emblem, IMPALA,
and the IMPALA Emblem are
trademarks and/or service marks of
General Motors LLC, its
subsidiaries, affiliates, or licensors.
This manual describes features that
may or may not be on the vehicle
because of optional equipment that
was not purchased on the vehicle,
model variants, country
specifications, features/applicationsthat may not be available in your
region, or changes subsequent to
the printing of this owner manual.
Refer to the purchase
documentation relating to your
specific vehicle to confirm the
features.
This vehicle is designed to operate
on gasoline or Compressed Natural
Gas (CNG).
Keep this manual in the vehicle for
quick reference.
Canadian Vehicle Owners
Propriétaires Canadiens
A French language manual can be
obtained from your dealer, at
www.helminc.com, or from:
On peut obtenir un exemplaire de
ce guide en français auprès du
concessionnaire ou à l'adresse
suivante:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
Using this Supplement
This supplement contains
information specific to the unique
components of the vehicle. It does
not explain everything you need to
know about the vehicle. Read this
supplement along with the owner
manual to learn about the vehicle's
features and controls.
Index
A good place to look for what you
need is the Index in back of this
supplement. It is an alphabetical list
of what is in the supplement, and
the page number where you will
find it.
Litho in U.S.A.
Part No. 23343095 A First Printing©2015 General Motors LLC. All Rights Reserved.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
4 Instruments and Controls
CNG fuel gauge readings are
affected by changes in fuel
temperature and fuel pressure.
See“Fuel Gauge” in the owner
manual.
Malfunction Indicator
Lamp (Check Engine
Light)
The malfunction indicator lamp is in
the instrument cluster.
This vehicle has been specifically
designed to illuminate this indicator
when emissions exceed acceptable
levels while operating on either
gasoline or CNG fuel.
The malfunction indicator lamp
comes on to indicate that there is a
problem and service is required.
Malfunctions often will be indicated
by the system before any problem is apparent. This system is also
designed to assist the service
technician in correctly diagnosing
any malfunction.
Caution
If the vehicle is continually driven
with this light on, the emission
controls might not work as well,
the vehicle fuel economy might
not be as good, and the engine
might not run as smoothly. This
could lead to costly repairs that
might not be covered by the
vehicle warranty.
This light should come on as a
check to show you it is working
when the ignition is on and the
engine is not running.
This light comes on during a
malfunction in one of two ways:
Light Flashing
A misfire condition has been
detected. A misfire increases
vehicle emissions and could damage the emission control
system on the vehicle. Diagnosis
and service might be required.
To prevent more serious damage to
the vehicle:
.
Reduce vehicle speed.
. Avoid hard accelerations.
. Avoid steep uphill grades.
If the light continues to flash, find a
safe place to stop and park the
vehicle. Turn the vehicle off, wait at
least 10 seconds, and restart the
engine. If the light is still flashing,
follow the previous steps and see
your dealer for service as soon as
possible.
Light On Steady
An emission control system
malfunction has been detected on
the vehicle. Diagnosis and service
might be required.
See the owner manual for more
information.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
6 Instruments and Controls
Vehicle Messages
Fuel System Messages
FUEL MODE UNAVAILABLE
This message displays when the
current fuel mode selected is empty
or unavailable. See“Fuel Selector
Switch” underFuel08. The vehicle
will switch fuel modes automatically.
This is usually due to a low fuel
condition of the fuel type selected or
the engine is not warm enough after
an initial engine start up.
This message will also appear if the
vehicle has initiated a gasoline
system maintenance routine.
A switch to CNG will not be
available until this routine is
complete.
This message can also appear if a
transition to CNG is attempted in
cold start conditions. See “Cold
Weather Starting” underStarting the
Engine 07. This message may also appear if
the CNG tank valve is unable to
open fully during some vehicle
operating conditions.
SERVICE FUEL SYSTEM PARK
IN OPEN AREA
This vehicle is equipped with a CNG
fuel system diagnostic to ensure
proper function. This message
displays when the CNG fuel system
requires service.
Park the vehicle in an outdoor open
area, do not start the engine, refuel,
or drive the vehicle. Have the
vehicle towed to an authorized GM
dealer for service.
See
Fuel System Leak 014.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
Driving and Operating 9
standards for general marketplace
vehicle usage; however, CNG is
available at both private and public
filling stations. We recommend use
of CNG that meets or exceeds SAE
J1616 specifications for fuel
composition and cleanliness. See
Filling the Tank (CNG)09.
Caution
Using below standard CNG fuel
quality may cause damage to the
CNG fuel system. Use only CNG
fuel meeting recommended CNG
fuel standards.
The main component of CNG is
methane, a highly flammable,
colorless gas. An odorant has been
added for detection through smell.
The smell is similar to that of rotten
eggs. The CNG in the vehicle is
stored under high pressure
(maximum 24 800kPa at 21 °C/
3,600 psig at 70 °F). Gas should
never be smelled unless it occurs
briefly during refueling. If gas is
smelled or a hissing sound is heard
at any other time, park in a well ventilated outdoor open area, shut
down the vehicle, and have it
serviced.
It may be possible to hear the fuel
flowing while the engine is running if
standing close to the pipework or
various fuel system components
(regulator, filter). This is normal and
should not be confused with a
hissing sound at fittings that may
indicate a fuel leak. If you suspect a
fuel leak, follow the instructions
under
Fuel System Leak 014.
Fuel Selector Switch
The fuel selector switch is on the
instrument panel left of the steering
wheel. When the ignition is in ON/
RUN, press
0to select between
gasoline and CNG. The indicator
light in the fuel selector switch
comes on when the vehicle is
running on CNG.
Certain conditions must be met in
order to switch between gasoline
and CNG. The vehicle will start up
on the last fuel that was selected.
When the fuel selector switch is
pressed, the indicator light will flash
during a fuel transition. If the fuel
transition is unsuccessful, the DIC
will display FUEL MODE
UNAVAILABLE. See Fuel System
Messages 06.
Filling the Tank (CNG)
{Warning
CNG is flammable and highly
explosive. You could be killed or
seriously injured if leaking natural
(Continued)

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
Driving and Operating 11
fill station as soon as it is full,
unless an auto shutoff feature
is used.
{Warning
If CNG tanks are filled to a higher
pressure than recommended and
then exposed to a much higher
ambient temperature
environment, expansion of the
gas caused by the temperature
change may cause pressure relief
devices on the vehicle CNG
tank(s) to release gas, as
designed. If an ignition source is
present, this could create a risk of
fire or explosion. If there is any
possibility that the tank has been
over pressurized, take steps to
relieve the excess pressure, such
as by driving or running the
vehicle in an outdoor open area
to remove some fuel.Make sure that your CNG vehicle is
properly maintained and repaired to
avoid elevated temperatures
surrounding the tank, since elevated
temperatures in the area of the tank
could also raise the CNG pressure
in the tank.
Consult materials available from
NGVAmerica - http://www.ngvc.org
and the Clean Vehicle
Education Foundation -
http://www.cleanvehicle.org on CNG
fueling stations for more information.
Ambient Temperature / Maximum
CNG Fill Pressure Compensation
Chart
To avoid the risk of fire or explosion
if an ignition source were present,
do not fill above the pressure level
that corresponds to the lowest
ambient temperature expected
during fueling.
Service Pressure 24 800 kPa
(3,600 psig) at 21 °C (70 °F).

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
Driving and Operating 13
dispenser to the fill valve and begin
refueling again. If a leak is still
present, replace the fill valve O-ring.
{Warning
Attempting to fill a CNG fuel
system that has a missing or
damaged O‐ring is dangerous.
Natural gas can leak. If the
natural gas is ignited, you or
others could be injured. Replace
the O‐ring before filling the tank.
Fill Valve O-RingTo replace the fill valve O-ring:
1. Carefully remove the O-ring from the groove in the fill
receptacle. A small flat-blade
or pointed tool can be used.
2. Make sure the groove is clean and free of dirt and debris.
3. Install the new O-ring in the groove in the fill receptacle.
Make sure the O-ring is
properly seated in the groove.
If a leak is still present after you
have replaced the O-ring, have an
authorized dealer inspect the
sealing O-ring in the fill receptacle.
If dirt or other debris is adhering to
the inside of the fuel fill receptacle,
gas may leak out after refueling.
If you need to add more fuel, repeat
the refueling procedure again.
See an authorized GM dealer for
replacement O-rings.
Fuel Filling Problems
If you experience very slow fill rates,
the CNG fuel filter in the fill valve
may require service. Slow fill rates
may also be caused by ice
formation on the fuel receptacle.
Use only CNG fuel meeting
recommended CNG fuel standards.
If you experience reduced range
during CNG operation and none of
the conditions described earlier in
this section apply, the CNG fuel tank
may require service. This may be
caused by the buildup of water, oil,
or debris inside the tank or an
inoperative tank valve. In either
case, take the vehicle to an
authorized GM dealer for service.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
14 Driving and Operating
Pressure Relief Devices
The CNG tank has pressure relief
devices that are designed to release
pressure if the CNG tank is
overheated or over pressurized.
If a pressure relief device releases
CNG, the CNG tank will be emptied
and will switch to gasoline,
if gasoline is available. A loud
rushing noise may be heard when
CNG is released.
In Case of a CNG Leak
If a CNG fuel leak is suspected, see
Fuel System Leak014.
Fuel System Leak
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
. Keep all smoking materials
and sources of ignition away
from the fuel system
components.
(Continued)
Warning (Continued)
.CNG is non-toxic but the
vapors are lighter than air
and can cause oxygen
depletion if they are
enclosed in a confined
space. Make sure there is
adequate ventilation and
use extreme caution if a
leak is suspected.
{Warning
If you smell a persistent natural
gas odor or hear a continual
hissing sound, there could be a
CNG leak. If the gas is
accidentally ignited, you or others
could be seriously injured or
killed. Do not start the engine or
drive the vehicle. Have the
vehicle towed to an authorized
GM dealer for service. A slight natural gas odor may be
detected for a few moments after
refueling. This is normal. You should
not be able to smell natural gas at
any other time. If you do, or if you
hear a hissing sound, the fuel
system may have a leak.
If natural gas is smelled or a hissing
sound is heard:
1. Park the vehicle in an outdoor open area and apply the
parking brake. Keep heat,
sparks, and flame away. Open
all the vehicle doors for
ventilation.
2. Turn the ignition to LOCK/OFF. Do not start the engine, refuel,
or drive the vehicle.
3. The manual shutoff is on the driver side of the vehicle in
front of the rear tire. See Fuel
System Components 017.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
Driving and Operating 15
A label is on the outside of the
vehicle near the manual shutoff
valve. Do not remove this label.
Turn the lever one-quarter turn
clockwise to turn off.
Do not drive the vehicle. Have the
vehicle towed to an authorized GM
dealer for service.Trailer Towing
The vehicle is neither designed nor
intended to tow a trailer.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
16 Vehicle Care
Vehicle Care
General Information
Accessories andModifications . . . . . . . . . . . . . . . . . 16
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . 16
Fuel System Components . . . . . 17
Wheels and Tires
Tire Changing . . . . . . . . . . . . . . . . . 19
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . 19
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . 20
General Information
Accessories and
Modifications
Adding accessories or making
modifications to the vehicle,
including to the CNG tank shields,
could cause damage and would not
be covered by the vehicle warranty.
If a CNG tank needs service or
repair, have only a qualified
technician perform the work. See
“Accessories and Modifications” in
the owner manual.
Vehicle Checks
Doing Your Own
Service Work
{Warning
Never try to do your own service
work on the Compressed Natural
Gas (CNG) fuel system. The CNG
fuel system operates under high
pressure. You can be injured and
the vehicle can be damaged if
you try to do your own service
work. Service and repair of this
system should only be performed
by a qualified dealer.