engine 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
Instruments and Controls 3
Instruments and
Controls
Warning Lights, Gauges, and
Indicators
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . 3
Malfunction Indicator Lamp(Check Engine Light) . . . . . . . . . . 4
Low Fuel Warning Light . . . . . . . . . 5
Information Displays
Driver Information
Center (DIC) . . . . . . . . . . . . . . . . . . . 5
Vehicle Messages
Fuel System Messages . . . . . . . . . 6
Warning Lights,
Gauges, and
Indicators
Fuel Gauge
The vehicle has a fuel gauge that
displays either gasoline or CNG fuel
level.
Metric
English
With the ignition on, the gasoline/
CNG fuel gauge indicates remaining
fuel in the tank for the fuel that is
being used. See “Fuel Selector
Switch” underFuel08.
To check the level of the fuel not
being used, see Driver Information
Center (DIC) 05.
For CNG, the fuel gauge has been
calibrated to display full at
approximately 24 800 kPa
(3,600 psig) and empty at
approximately 2 758 kPa (400 psig).

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 7
Driving and
Operating
Driving Information
Vehicle Load Limits . . . . . . . . . . . . . 7
Starting and Operating
Starting the Engine . . . . . . . . . . . . . . 7
Ride Control Systems
Traction Control/ElectronicStability Control . . . . . . . . . . . . . . . . 8
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Filling the Tank (CNG) . . . . . . . . . . 9
Fuel System Leak . . . . . . . . . . . . . 14
Trailer Towing
Trailer Towing . . . . . . . . . . . . . . . . . . 15
Driving Information
Vehicle Load Limits
Caution
Loose items stored in the cargo
area may damage the CNG fuel
tank and fuel system
components. Secure all items in
the cargo area to avoid shifting
and any damage to the CNG fuel
tank and CNG fuel tank
components.
Starting and
Operating
Starting the Engine
Starting the engine in a CNG
vehicle is similar to starting a
gasoline engine. See “Starting the
Engine” in the owner manual.
Fuel Selection
A switch allows the selection of fuel.
See Fuel 08. The vehicle typically
defaults to the fuel used on the last
key cycle.
If a tank refill has occurred after an
automatic low fuel level transition
from one fuel to another, CNG to
gasoline for example, the vehicle
recognizes the refill and if conditions
are met, will start on the fuel last
selected on the switch.
To protect engine and gasoline fuel
system components, an automatic
switch to gasoline may occur at any
time. The vehicle will transition back
to CNG automatically once the
gasoline system has run for a pre–
set time.

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
8 Driving and Operating
Cold Weather Starting
If the outside temperature is below
2 °C (35 °F), the engine may start on
gasoline when CNG is selected.
After starting on gasoline, the
vehicle will automatically transition
to CNG operation after a set amount
of warm-up time.
Using the engine heater,
if equipped, may make it easier to
start. See“Engine Heater” in the
owner manual.
. Turn off all electrical
accessories.
. Do not hold the ignition switch in
START for more than
15 seconds.
Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See “Add-On Electrical
Equipment” in the owner manual.
Ride Control Systems
Traction Control/
Electronic Stability
Control
This vehicle has Traction Control
System (TCS) and StabiliTrak®
electronic stability control systems.
These systems are enabled
automatically and StabiliTrak cannot
be turned off. To turn off TCS, see
“Traction Control/Electronic Stability
Control”in the owner manual.
Fuel
If a fuel leak is suspected, see Fuel
System Leak 014.
. If the vehicle runs out of CNG or
gasoline, it will automatically
switch to the other fuel system,
if there is fuel.
. If it takes unusually long to fill
the CNG cylinder, the fuel fill
receptacle may be clogged.
Contact your dealer for
inspection and/or replacement.
See “Fuel Filling Problems” in
Filling the Tank (CNG) 09.
This vehicle is designed to operate
on gasoline or CNG and has a
gasoline tank and a CNG fuel
storage system. See “Fuel”in the
owner manual for gasoline
information.
The general marketplace fuel quality
of CNG (for motor vehicles) in the
state of California should be in
compliance with Title 13 California
Code of Regulations, Section
2292.5. The remaining regions of
North America do not employ
regulated CNG fuel quality

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
10 Driving and Operating
Warning (Continued)
gas is ignited. If you suspect a
leak, do not start the engine or
drive the vehicle. Have the
vehicle immediately towed,
inspected, and repaired by an
authorized GM dealer.
Before filling either fuel tank, turn off
the engine.
The gasoline tank is filled through
the standard fill pipe. See “Filling
the Tank” under“Fuel” in the owner
manual.
The CNG fill receptacle is behind
the fuel door on the passenger side
above the gasoline cap.
Refueling Procedure
There are two methods of refueling:
fast fill or time fill. Fast fill is
normally used in fuel stations for
natural gas vehicles. It takes about
two to five minutes to fill up the fuel
tank. Time fill is done with a
refueling appliance, including
residential appliances, or a time-fill
post provided by the fleet operator.
Refueling time varies depending
upon the refueling system used —
consult with the refueling station
attendant or system provider.
Always observe all safety
recommendations and operating
instructions on the refueling
equipment. If a 24 800 kPa
(3,600 psig) nozzle is not available,
a 20 684 kPa (3,000 psig) nozzle
may be connected to the vehicle.
A fuel nozzle less than 7.6 cm (3 in)
long may be difficult to disengage
after dispensing CNG. During fueling, CNG needs to be
delivered to the vehicle at the
appropriate pressure in relationship
to the ambient temperature. This
can be done automatically by a
temperature compensation system
on the CNG fuel dispenser or
manually by stopping the CNG fill at
a recommended pressure related to
the ambient temperature
compensation chart. GM
recommends that customers use
CNG fueling stations that have a
temperature compensation system
whenever possible. Check with the
fuel station. If one is not available,
see the temperature compensation
chart that follows in this section to
choose the appropriate fill pressure
for the ambient temperature. In
addition, fill only to the pressure
level for the lowest ambient
temperature anticipated during
fueling.
Leaving a vehicle connected to a
time fill station can cause the tank
to be filled to a higher pressure than
recommended, especially when
outside temperatures fluctuate.
Disconnect the vehicle from the time

Chevrolet Impala Bi-Fuel (Gasoline/CNG) Supplement (GMNA-Localizing-U.
S/Canada-9087624) - 2016 - CRC - 8/17/15
12 Driving and Operating
Depending on CNG fill station
equipment/performance, CNG fill
volume will vary. This will affect
overall vehicle range.Put the vehicle into P (Park) and
turn off the engine prior to refueling.
Remove the dust cap from the
receptacle, clean off any dirt or
debris on the receptacle, and followthe refueling instructions on the
pump or provided by the station
operator.
Refueling will stop automatically
when the tank is full. Wait for the
high pressure fuel to be purged from
the hose before disconnecting. See
the station operator for information
on how the line is purged. To
disconnect the vehicle from the
refueling station, remove the nozzle
from the fill receptacle.
A momentary release of CNG will
occur when the nozzle is released.
This is normal.
Put the fill valve dust cap on
securely and close the fuel
filler door.
If fuel or vapor is heard or seen
leaking from the nozzle-fill
receptacle connection, stop
refueling immediately. Dirt or other
debris may be preventing a positive
connection. Turn off the refueling
dispenser, disconnect the nozzle,
and inspect the fill receptacle for a
missing, damaged, dirty, or worn
O-ring. Reconnect the refueling

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
18 Vehicle Care
Manual Shutoff Valve
Locate the manual shutoff valve so
that it can be found quickly if it is
needed.
The manual shutoff valve is on the
driver side of the vehicle in front of
the rear tire.
A label is on the outside of the
vehicle near the manual shutoff
valve. Do not remove this label.To turn off the valve, turn the lever
one-quarter turn clockwise. Turn it
counterclockwise to turn the valve
back on.
Turn off the valve if a fuel leak is
suspected or the vehicle is involved
in an accident. This valve, when
turned, will stop CNG flow to the
engine.High Pressure CNG Fuel Filter
The high pressure CNG fuel filter is
under the rear of the vehicle. This
filter must have the water drained
and the filter element must also be
replaced at specific service
intervals. See
Maintenance
Schedule 021.