fuel consumption DODGE TOWN AND COUNTRY 2004 Service Manual

FUEL REQUIREMENTS
The vehicle will operate on both unleaded gasoline
with an octane rating of 87, or E-85 fuel, or any mix-
ture of these two.
For best results, a refueling pattern that alternates
between E-85 and unleaded gasoline should be
avoided. When you do switch fuels, it is recom-
mended that
²you do not switch when the fuel gauge indicates
less than 1/4 full
²you do not add less than 5 gallons when refuel-
ing
²you operate the vehicle immediately after refuel-
ing for a period of at least 5 minutes
Observing these precautions will avoid possible
hard starting and/or significant deterioration in
driveability during warm up.
FFV STARTING
The characteristics of E-85 fuel make it unsuitable
for use when ambient temperatures fall below 0ÉF. In
the range of 0ÉF to 32ÉF, you may experience an
increase in the time it takes for your engine to start,
and a deterioration in driveability (sags and/or hesi-
tations) until the engine is fully warmed up.
Engine Operating on E-85 Fuel
If vehicle operates on E-85 fuel either full or part-
time, use only MopartFlexible Fuel 5W-30 engine oil
or an equivalent that meets DaimlerChrysler Stan-
dard MS-9214. Equivalent commercial Flexible Fuel
engine oils may be labeled as Multi-Fuel, Variable
Fuel, Flexible Fuel, etc. These engine oils may be
satisfactory if they meet the DaimlerChrysler Stan-
dard.
SAE 5W-30 engine oil is preferred for use in Flex-
ible Fuel engines.
CAUTION: If Flexible Fuel engine oil is not used
when using E-85 fuel, engine wear or damage may
result.
CRUISING RANGE
Because E-85 fuel contains less energy per gallon
than gasoline, you will experience an increase in fuel
consumption. You can expect your MPG and your
driving range to decrease by about 30% compared to
gasoline operation.
DESCRIPTION - AUTOMATIC/MANUAL
TRANSAXLE FLUID
NOTE: Refer to the maintenance schedules for the
recommended maintenance (fluid/filter change)
intervals for these transaxles.NOTE: All transaxles have a common transmission
and differential sump. Filling the transaxle accom-
modates the differential as well.
TRANSMISSION FLUID
MopartATF+4 (Automatic Transmission Fluid) is
required in the 41TE automatic and T850 manual
transaxles. Substitute fluids can induce transmission
problems and/or failure.
MopartATF+4 (Automatic Transmission Fluid)
when new is red in color. The ATF is dyed red so it
can be identified from other fluids used in the vehicle
such as engine oil or antifreeze. The red color is not
permanent and is not an indicator of fluid condition.
As the vehicle is driven, the ATF will begin to look
darker in color and may eventually become brown.
This is normal.ATF+4 also has a unique odor that
may change with age. Consequently,odor and color
cannot be used to indicate the fluid condition
or the need for a fluid change.
FLUID ADDITIVES
DaimlerChrysler strongly recommends against the
addition of any fluids to the transmission, other than
those automatic transmission fluids listed above.
Exceptions to this policy are the use of special dyes
to aid in detecting fluid leaks.
Various ªspecialº additives and supplements exist
that claim to improve shift feel and/or quality. These
additives and others also claim to improve converter
clutch operation and inhibit overheating, oxidation,
varnish, and sludge. These claims have not been sup-
ported to the satisfaction of DaimlerChrysler and
these additivesmust not be used.The use of trans-
mission ªsealersº should also be avoided, since they
may adversely affect the integrity of transmission
seals.
DESCRIPTION - FUEL REQUIREMENTS
Your engine is designed to meet all emissions reg-
ulations and provide excellent fuel economy and per-
formance when using high quality unleaded gasoline
having an octane rating of 87. The use of premium
gasoline is not recommended. The use of premium
gasoline will provide no benefit over high quality reg-
ular gasoline, and in some circumstances may result
in poorer performance.
Light spark knock at low engine speeds is not
harmful to your engine. However, continued heavy
spark knock at high speeds can cause damage and
immediate service is required. Engine damage result-
ing from operation with a heavy spark knock may
not be covered by the new vehicle warranty.
Poor quality gasoline can cause problems such as
hard starting, stalling and hesitations. If you experi-
0 - 4 LUBRICATION & MAINTENANCERS
FLUID TYPES (Continued)

through to the rear wheels. The rear driveline mod-
ule, with the BOC, will perform the same as a front
wheel drive vehicle during these events. The gear
ratio offset between the front and rear differentials
force the BOC into the overrunning mode most of thetime. This allows BOC to significantly reduce the
rolling resistance of the vehicle, which improves fuel
consumption, allows the downsizing of the driveline
components, and prevents the PTU and propshaft
joints from overheating.
Fig. 28 Bi-directional Overrunning Clutch and Viscous Coupler
1 - POWERFLOW - BOC OVERUNNING 6 - VISCOUS COUPLER
2 - POWERFLOW - BOC LOCKED 7 - BOC ROLLER CAGE
3 - BOC GROUND TAB 8 - BOC INPUT SHAFT
4 - FRICTION BRAKE SHOES 9 - INPUT FLANGE
5 - BOC ROLLERS
RSREAR DRIVELINE MODULE3-35
BI-DIRECTIONAL OVERRUNNING CLUTCH (Continued)

FUEL INJECTOR MECHANICAL MALFUNCTIONS
The PCM cannot determine if a fuel injector is
clogged, the needle is sticking or if the wrong injector
is installed. However, these could result in a rich or
lean condition causing the PCM to store a diagnostic
trouble code for either misfire, an oxygen sensor, or
the fuel system.
EXCESSIVE OIL CONSUMPTION
Although the PCM monitors engine exhaust oxygen
content when the system is in closed loop, it cannot
determine excessive oil consumption.
THROTTLE BODY AIR FLOW
The PCM cannot detect a clogged or restricted air
cleaner inlet or filter element.
VACUUM ASSIST
The PCM cannot detect leaks or restrictions in the
vacuum circuits of vacuum assisted engine control
system devices. However, these could cause the PCM
to store a MAP sensor diagnostic trouble code and
cause a high idle condition.
PCM SYSTEM GROUND
The PCM cannot determine a poor system ground.
However, one or more diagnostic trouble codes may
be generated as a result of this condition. The mod-
ule should be mounted to the body at all times,
including when diagnostics are performed.
PCM CONNECTOR ENGAGEMENT
The PCM may not be able to determine spread or
damaged connector pins. However, it might store
diagnostic trouble codes as a result of spread connec-
tor pins.
DESCRIPTION - MONITORED SYSTEMS
There are new electronic circuit monitors that
check fuel, emission, engine and ignition perfor-
mance. These monitors use information from various
sensor circuits to indicate the overall operation of the
fuel, engine, ignition and emission systems and thus
the emissions performance of the vehicle.
The fuel, engine, ignition and emission systems
monitors do not indicate a specific component prob-
lem. They do indicate that there is an implied prob-
lem within one of the systems and that a specific
problem must be diagnosed.
If any of these monitors detect a problem affecting
vehicle emissions, the Malfunction Indicator (Check
Engine) Lamp will be illuminated. These monitors
generate Diagnostic Trouble Codes that can be dis-
played with the a DRBIIItscan tool.
The following is a list of the system monitors:
²EGR Monitor (if equipped)²Misfire Monitor
²Fuel System Monitor
²Oxygen Sensor Monitor
²Oxygen Sensor Heater Monitor
²Catalyst Monitor
²Evaporative System Leak Detection Monitor (if
equipped)
Following is a description of each system monitor,
and its DTC.
Refer to the appropriate Powertrain Diagnos-
tics Procedures manual for diagnostic proce-
dures.
OXYGEN SENSOR (O2S) MONITOR
Effective control of exhaust emissions is achieved
by an oxygen feedback system. The most important
element of the feedback system is the O2S. The O2S
is located in the exhaust path. Once it reaches oper-
ating temperatures of 300É to 350ÉC (572É to 662ÉF),
the sensor generates a voltage that is inversely pro-
portional to the amount of oxygen in the exhaust.
The information obtained by the sensor is used to
calculate the fuel injector pulse width. The PCM is
programmed to maintain the optimum air/fuel ratio.
At this mixture ratio, the catalyst works best to
remove hydrocarbons (HC), carbon monoxide (CO)
and nitrous oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the
EGR (if equipped), Catalyst and Fuel Monitors.
The O2S may fail in any or all of the following
manners:
²Slow response rate
²Reduced output voltage
²Dynamic shift
²Shorted or open circuits
Response rate is the time required for the sensor to
switch from lean to rich once it is exposed to a richer
than optimum A/F mixture or vice versa. As the sen-
sor starts malfunctioning, it could take longer to
detect the changes in the oxygen content of the
exhaust gas.
The output voltage of the O2S ranges from 0 to 1
volt (voltages are offset by 2.5 volts on NGC vehi-
cles). A good sensor can easily generate any output
voltage in this range as it is exposed to different con-
centrations of oxygen. To detect a shift in the A/F
mixture (lean or rich), the output voltage has to
change beyond a threshold value. A malfunctioning
sensor could have difficulty changing beyond the
threshold value.
OXYGEN SENSOR HEATER MONITOR
If there is an oxygen sensor (O2S) DTC as well as
a O2S heater DTC, the O2S heater fault MUST be
repaired first. After the O2S fault is repaired, verify
that the heater circuit is operating correctly.
25 - 6 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)