
²Ethanel content learn is takeng place and the
ethenal used once flag is set
SuspendÐThe Task Manager does not mature a
catalyst fault if any of the following are present:
²Oxygen Sensor Monitor, Priority 1
²Upstream Oxygen Sensor Heater, Priority 1
²EGR Monitor, Priority 1
²EVAP Monitor, Priority 1
²Fuel System Monitor, Priority 2
²Misfire Monitor, Priority 2
DESCRIPTION - VEHICLE EMISSION CONTROL
INFORMATION LABEL
All models have a Vehicle Emission Control Infor-
mation (VECI) Label. Chrysler permanently attaches
the label in the engine compartment. It cannot be
removed without defacing information and destroying
the label.
The label contains the vehicle's emission specifica-
tions and vacuum hose routings. All hoses must be
connected and routed according to the label.
DESCRIPTION - TRIP DEFINITION
A ªTripº means vehicle operation (following an
engine-off period) of duration and driving mode such
that all components and systems are monitored at
least once by the diagnostic system. The monitors
must successfully pass before the PCM can verify
that a previously malfunctioning component is meet-
ing the normal operating conditions of that compo-
nent. For misfire or fuel system malfunction, the
MIL may be extinguished if the fault does not recur
when monitored during three subsequent sequential
driving cycles in which conditions are similar to
those under which the malfunction was first deter-
mined.
Anytime the MIL is illuminated, a DTC is stored.
The DTC can self erase only when the MIL has been
extinguished. Once the MIL is extinguished, the
PCM must pass the diagnostic test for the most
recent DTC for 40 warm-up cycles (80 warm-up
cycles for the Fuel System Monitor and the Misfire
Monitor) . A warm-up cycle can best be described by
the following:
²The engine must be running
²A rise of 40ÉF in engine temperature must occur
from the time when the engine was started
²Engine coolant temperature must reach at least
160ÉF
²A ªdriving cycleº that consists of engine start up
and engine shut off.
Once the above conditions occur, the PCM is con-
sidered to have passed a warm-up cycle. Due to the
conditions required to extinguish the MIL and erase
the DTC, it is most important that after a repair hasbeen made, all DTC's be erased and the repair veri-
fied.
OPERATION - NON-MONITORED CIRCUITS
The PCM does not monitor all circuits, systems
and conditions that could have malfunctions causing
driveability problems. However, problems with these
systems may cause the PCM to store diagnostic trou-
ble codes for other systems or components. For exam-
ple, a fuel pressure problem will not register a fault
directly, but could cause a rich/lean condition or mis-
fire. This could cause the PCM to store an oxygen
sensor or misfire diagnostic trouble code.
The major non-monitored circuits are listed below
along with examples of failures modes that do not
directly cause the PCM to set a DTC, but for a sys-
tem that is monitored.
FUEL PRESSURE
The fuel pressure regulator controls fuel system
pressure. The PCM cannot detect a clogged fuel
pump inlet filter, clogged in-line fuel filter, or a
pinched fuel supply or return line. However, these
could result in a rich or lean condition causing the
PCM to store an oxygen sensor or fuel system diag-
nostic trouble code.
SECONDARY IGNITION CIRCUIT
The PCM cannot detect an inoperative ignition coil,
fouled or worn spark plugs, ignition cross firing, or
open spark plug cables.
CYLINDER COMPRESSION
The PCM cannot detect uneven, low, or high engine
cylinder compression.
EXHAUST SYSTEM
The PCM cannot detect a plugged, restricted or
leaking exhaust system. It may set a EGR or Fuel
system fault or O2S.
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.
RSEMISSIONS CONTROL25-5
EMISSIONS CONTROL (Continued)

DIAGNOSIS AND TESTING - VEHICLE DOES
NOT FILL
CONDITION POSSIBLE CAUSES CORRECTION
Pre-Mature Nozzle Shut-Off Defective fuel tank assembly
components.Fill tube improperly installed
(sump)
Fill tube hose pinched.
Check valve stuck shut.
Control valve stuck shut.
Defective vapor/vent components. Vent line from control valve to
canister pinched.
Vent line from canister to vent
filter pinched.
Canister vent valve failure
(requires double failure,
plugged to LDP and
atmosphere).
Leak detection pump failed
closed.
Leak detection pump filter
plugged.
On-Board diagnostics evaporative
system leak test just conducted.Canister vent valve vent
plugged to atmosphere.
engine still running when
attempting to fill (System
designed not to fill).
Defective fill nozzle. Try another nozzle.
Fuel Spits Out Of Filler
Tube.During fill. See Pre-Mature Shut-Off.
At conclusion of fill. Defective fuel handling
component. (Check valve stuck
open).
Defective vapor/vent handling
component.
Defective fill nozzle.
25 - 16 EVAPORATIVE EMISSIONSRS
ORVR (Continued)

Once the auto shutdown and fuel pump relays
have been energized, the PCM determines the fuel
injector pulse width based on the following:
± engine coolant temperature
± manifold absolute pressure
± intake air temperature
± engine revolutions
± throttle position
The PCM determines the spark advance based on
the following:
± engine coolant temperature
± crankshaft position
± intake air temperature
± manifold absolute pressure
± throttle position
Engine Warm-Up Modeþ This is an open loop
mode. The PCM adjusts injector pulse width and
controls injector synchronization by controlling the
fuel injectors' ground paths. The PCM adjusts igni-
tion timing and engine idle speed. The PCM adjusts
the idle speed by controlling the idle air control
motor.
Cruise or Idle Modeþ When the engine is at
normal operating temperature, this is a closed loop
mode.
Acceleration Modeþ This is a closed loop mode.
The PCM recognizes an increase in throttle position
and a decrease in Manifold Vacuum as engine load
increases. In response, the PCM increases the in-
jector pulse width to meet the increased load. The
A/C compressor may be de-energized for a short
period of time.
Decelerationþ This is a closed loop mode. The
PCM recognizes a decrease in throttle position and
an increase in Manifold Vacuum as engine load
decreases. In response, the PCM decreases the
injector pulse width to meet the decreased load.
Full injector shut off may be obtained during high
speed deceleration.
Wide Open Throttle Modeþ This is an open
loop mode. The throttle position sensor notifies the
PCM of a wide open throttle condition. Once a wide
open throttle is sensed, the PCM de-energizes the
A/C compressor clutch relay for 20 seconds.
3.2.5 NON-MONITORED CIRCUITS
The PCM does not monitor the following circuits,
systems, and conditions even though they could
have malfunctions that result in driveability prob-
lems. A diagnostic code may not be displayed for the
following conditions. However, problems with these
systems may cause a diagnostic code to be displayed
for other systems. For example, a fuel pressure
problem will not register a diagnostic code directly,
but could cause a rich or lean condition. This couldcause an oxygen sensor, fuel system, or misfire
monitor trouble code to be stored in the PCM.
Engine Timingþ The PCM cannot detect an
incorrectly indexed timing chain, camshaft
sprocket, or crankshaft sprocket. The PCM also
cannot detect an incorrectly indexed distributor.(*)
Fuel Pressureþ Fuel pressure is controlled by
the fuel pressure regulator. The PCM cannot detect
a clogged fuel pump inlet filter, clogged in-line filter,
or a pinched fuel supply.(*)
Fuel Injectorsþ The PCM cannot detect if a fuel
injector is clogged, the pintle is sticking, or the
wrong injectors are installed.(*)
Fuel Requirementsþ Poor quality gasoline can
cause problems such as hard starting, stalling, and
stumble. Use of methanol-gasoline blends may re-
sult in starting and driveability problems. See indi-
vidual symptoms and their definitions in Section
6.0 (Glossary of Terms).
PCM Groundsþ The PCM cannot detect a poor
system ground. However, a diagnostic trouble code
may be stored in the PCM as a result of this
condition.
Throttle Body Air Flowþ The PCM cannot
detect a clogged or restricted air cleaner inlet or
filter element.(*)
Exhaust Systemþ The PCM cannot detect a
plugged, restricted, or leaking exhaust system.(*)
Cylinder Compressionþ The PCM cannot de-
tect uneven, low, or high engine cylinder compres-
sion.(*)
Excessive Oil Consumptionþ Although the
PCM monitors the exhaust stream oxygen content
through the oxygen sensor when the system is in a
closed loop, it cannot determine excessive oil con-
sumption.
NOTE: ANY OF THESE CONDITIONS
COULD RESULT IN A RICH OR LEAN
CONDITION CAUSING AN OXYGEN SENSOR
TROUBLE CODE TO BE STORED IN THE
PCM, OR THE VEHICLE MAY EXHIBIT ONE
OR MORE OF THE DRIVEABILITY
SYMPTOMS LISTED IN THE TABLE OF
CONTENTS.
3.2.6 SKIS OVERVIEW
The Sentry Key Immobilizer System (SKIS) is
designed to prevent unauthorized vehicle opera-
tion. The system consists of a Sentry Key Immobi-
lizer Module (SKIM), ignition key(s) equipped with
a transponder chip and PCM. When the ignition
switch is turned on, the SKIM interrogates the
ignition key. If the ignition key is Valid or Invalid,
the SKIM sends a PCI Bus message to the PCM
indicating ignition key status. Upon receiving this
5
GENERAL INFORMATION

Symptom:
P0171-1/1 FUEL SYSTEM LEAN
When Monitored and Set Condition:
P0171-1/1 FUEL SYSTEM LEAN
When Monitored: With the engine running in closed loop mode, the ambient/battery
temperature above 20 deg. F and altitude below 8000 ft.
Set Condition: If the PCM multiplies short term compensation by long term adaptive and
a certain percentage is exceeded for two trips, a freeze frame is stored, the MIL illuminates
and a trouble code is stored.
POSSIBLE CAUSES
INTERMITTENT CONDITION
RESTRICTED FUEL SUPPLY LINE
FUEL PUMP INLET STRAINER PLUGGED
FUEL PUMP MODULE
O2 SENSOR
O2 SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
O2 SENSOR HEATER OPERATION
TPS VOLTAGE GREATER THAN 0.92 VOLTS WITH THROTTLE CLOSED
TP SENSOR SWEEP
MAP SENSOR OPERATION
ECT SENSOR OPERATION
ENGINE MECHANICAL PROBLEM
FUEL FILTER/PRESSURE REGULATOR (HIGH)
PCM
TEST ACTION APPLICABILITY
1NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
Turn the ignition on.
With the DRBIIIt, read DTC's.
Is the Good Trip displayed and equal to zero?All
Ye s®Go To 2
No®Go To 16
90
DRIVEABILITY - GAS

TEST ACTION APPLICABILITY
2Warning: The fuel system is under a constant pressure (even with the engine
off). Before testing or servicing any fuel system hose, fitting or line, the fuel
system pressure must be released.
Install a fuel pressure gauge to the fuel rail.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Turn the ignition off.
Choose a conclusion that best matches your fuel pressure reading.All
Within Specification
Go To 3
Above Specification
Replace the fuel filter/pressure regulator.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Below Specification
Go To 13
Caution: Stop All Actuations.
3 Turn the ignition on
With the DRBIIIt, read the O2 Sensor voltage.
Is the voltage between 0.4 to 0.6 volts?All
Ye s®Go To 4
No®Go To 10
4 Turn the ignition off.
NOTE: Wait a minimum of 10 minutes to allow the O2 Sensor to cool down
before continuing the test. Allow the O2 Sensor voltage to stabilize between
0.4 to 0.6 volts.
Turn the ignition on.
With the DRBIIIt, actuate the O2 Heater Test.
With the DRBIIIt, monitor O2 Sensor voltage for at least 2 minutes.
Does the voltage stay between 0.4 and 0.6All
Ye s®Replace the O2 Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 5
5 Turn the ignition on.
With the DRBIIIt, read TP Sensor voltage.
NOTE: The throttle must be against the stop.
Is the voltage 0.92 or less with the Throttle closed?All
Ye s®Go To 6
No®Check for a binding throttle condition. If OK, replace the Throttle
Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
91
DRIVEABILITY - GAS
P0171-1/1 FUEL SYSTEM LEAN ÐContinued

Symptom:
P0172-1/1 FUEL SYSTEM RICH
When Monitored and Set Condition:
P0172-1/1 FUEL SYSTEM RICH
When Monitored: With the engine running in closed loop mode, the ambient/battery
temperature above 20 deg. F and altitude below 8000 ft.
Set Condition: If the PCM multiplies short term compensation by long term adaptive and
the result is below a certain value for two trips, a freeze frame is stored, the MIL
illuminates and a trouble code is stored.
POSSIBLE CAUSES
INTERMITTENT CONDITION
O2 SENSOR HEATER OPERATION
O2 SENSOR
EVAP PURGE SOLENOID OPERATION
O2 SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
O2 SENSOR SIGNAL CIRCUIT OPEN
TPS VOLTAGE GREATER THAN 0.92 VOLTS WITH THROTTLE CLOSED
TP SENSOR SWEEP
MAP SENSOR OPERATION
ECT SENSOR OPERATION
ENGINE MECHANICAL PROBLEM
FUEL FILTER/PRESSURE REGULATOR (HIGH)
PCM
TEST ACTION APPLICABILITY
1NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
Turn the ignition on.
With the DRBIIIt, read DTC's.
Is the Good Trip displayed and equal to zero?All
Ye s®Go To 2
No®Go To 15
95
DRIVEABILITY - GAS

TEST ACTION APPLICABILITY
2Warning: The fuel system is under a constant pressure (even with the engine
off). Before testing or servicing any fuel system hose, fitting or line, the fuel
system pressure must be released.
Install a fuel pressure gauge to the fuel rail.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Turn the ignition off.
Choose a conclusion that best matches your fuel pressure reading.All
Within Specification
Go To 3
Above Specification
Replace the fuel filter/pressure regulator.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Caution: Stop All Actuations.
3 Turn the ignition on
With the DRBIIIt, read the O2 Sensor voltage.
Is the voltage between 0.4 to 0.6 volts?All
Ye s®Go To 4
No®Go To 11
4 Turn the ignition off.
NOTE: Wait a minimum of 10 minutes to allow the O2 Sensor to cool down
before continuing the test. Allow the O2 Sensor voltage to stabilize between
0.4 to 0.6 volts.
Turn the ignition on.
With the DRBIIIt, actuate the O2 Heater Test.
With the DRBIIIt, monitor O2 Sensor voltage for at least 2 minutes.
Does the voltage stay between 0.4 and 0.6All
Ye s®Replace the O2 Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 5
5 Turn the ignition off.
Disconnect the hoses at the Evap Purge Solenoid.
Using a hand vacuum pump, apply 10 inches of vacuum to the Evap Purge Solenoid
vacuum source port on the component side.
Did the Evap Purge Solenoid hold vacuum?All
Ye s®Go To 6
No®Replace the EVAP Purge Solenoid.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
96
DRIVEABILITY - GAS
P0172-1/1 FUEL SYSTEM RICH ÐContinued

TEST ACTION APPLICABILITY
2 Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose, fitting or line,
the fuel system pressure must be released.
Install a fuel pressure gauge to the fuel rail test port.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Choose a conclusion that best matches your fuel pressure reading.All
Below Specification
Go To 3
Within Specification
Go To 5
Above Specification
Replace the fuel filter/fuel pressure regulator.
Perform POWERTRAIN VERIFICATION TEST VER-1.
Caution: Stop All Actuations.
3 Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose, fitting or line,
the fuel system pressure must be released.
Raise vehicle on hoist, and disconnect the fuel pressure line at the fuel pump module.
Install special 5/169fuel line adapter tool #6539 between disconnected fuel line and
the fuel pump module.
Attach a fuel pressure test gauge to the9T9fitting on tool #6539.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Is the fuel pressure within specification now?All
Ye s®Repair/replace fuel supply line as necessary.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Go To 4
Caution: Stop All Actuations.
4 Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose,fitting or line,
the fuel system pressure must be released.
Remove the Fuel Pump Module and inspect the Fuel Inlet Strainer.
Is the Fuel Inlet Strainer plugged?All
Ye s®Replace the Fuel Pump Inlet Strainer.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER-1.
228
DRIVEABILITY - GAS
*CHECKING FUEL DELIVERY ÐContinued