fuel pump CHRYSLER VOYAGER 2001 Service Manual

EXHAUST GAS RECIRCULATION
TABLE OF CONTENTS
page page
EXHAUST GAS RECIRCULATION
DESCRIPTION............................3
OPERATION.............................3
VA LV E
DESCRIPTION............................3
OPERATION.............................4REMOVAL...............................4
INSTALLATION............................4
VALVE COOLER
DESCRIPTION............................4
REMOVAL...............................4
INSTALLATION............................5
EXHAUST GAS
RECIRCULATION
DESCRIPTION
The EGR system reduces oxides of nitrogen (NOx)
in the engine exhaust. This is accomplished by allow-
ing a predetermined amount of hot exhaust gas to
recirculate and dilute the incoming fuel/air mixture.
A malfunctioning EGR system can cause engine
stumble, sags, or hesitation, rough idle, engine stall-
ing and poor driveability.
OPERATION
The system consists of:
²An EGR valve assembly. The valve is located on
the rear of the engine above the exhaust manfiold.
²An EGR solenoid.The EGR solenoid controls the
ªon timeº of the EGR valve.
²The ECM operates the EGR solenoid. The ECM
is located inside the vehicle under the instrument
panel.
²An EGR tube connects a passage in the EGR
valve to the rear of the exhaust manifold.
²The vacuum pump supplies vacuum for the EGR
solenoid and the EGR valve. This pump also supplies
vacuum for operation of the power brake boosterb
and the heating and air conditioning system. The
pump is located internally in the front of the engine
block and is driven by the crankshaft gear.
²Vacuum lines and hoses connect the various
components.
When the ECM supplies a variable ground signal
to the EGR solenoid, EGR system operation starts to
occur. The ECM will monitor and determine when tosupply and remove this variable ground signal. This
will depend on inputs from the engine coolant tem-
perature, throttle position and engine speed sensors.
When the variable ground signal is supplied to the
EGR solenoid, vacuum from the vacuum pump will
be allowed to pass through the EGR solenoid and on
to the EGR valve with a connecting hose.
Exhaust gas recirculation will begin in this order
when:
²The ECM determines that EGR system opera-
tion is necessary.
²The engine is running to operate the vacuum
pump.
²A variable ground signal is supplied to the EGR
solenoid.
²Variable vacuum passes through the EGR sole-
noid to the EGR valve.
²The inlet seat (poppet valve) at the bottom of
the EGR valve opens to dilute and recirculate
exhaust gas back into the intake manifold.
The EGR system will be shut down by the ECM
after 60 seconds of continuous engine idling to
improve idle quality.
VA LV E
DESCRIPTION
The EGR system consists of (Fig. 1):
²EGR valve
²EGR tube
²Vacuum hoses
²EGR cooler
²EGR solenoid
RGEXHAUST GAS RECIRCULATION25a-3

TABLE OF CONTENTS - Continued
P0325-KNOCK SENSOR #1 CIRCUIT......................................113
P0340-NO CAM SIGNAL AT PCM.........................................116
P0351-IGNITION COIL #1 PRIMARY CIRCUIT..............................121
P0352-IGNITION COIL #2 PRIMARY CIRCUIT..............................121
P0353-IGNITION COIL #3 PRIMARY CIRCUIT..............................121
P0401 - EGR SYSTEM FAILURE.........................................124
P0403 - EGR SOLENOID CIRCUIT........................................128
P0420-1/1 CATALYTIC CONVERTER EFFICIENCY...........................131
P0441-EVAP PURGE FLOW MONITOR....................................133
P0442-EVAP LEAK MONITOR MEDIUM (.040) LEAK DETECTED...............136
P0455-EVAP LEAK MONITOR LARGE LEAK DETECTED.....................136
P0456 - EVAP LEAK MONITOR SMALL LEAK DETECTED....................136
P0443-EVAP PURGE SOLENOID CIRCUIT.................................139
P0460-FUEL LEVEL UNIT NO CHANGE OVER MILES........................142
P0462-FUEL LEVEL SENDING UNIT VOLTS TOO LOW.......................145
P0463-FUEL LEVEL SENDING UNIT VOLTS TOO HIGH......................145
P0500-NO VEHICLE SPEED SIGNAL (3SP AUTO AND MANUAL
TRANSMISSIONS).....................................................147
P0500-NO VEHICLE SPEED SIGNAL (4SP AUTO TRANS)....................150
P0505-IDLE AIR CONTROL MOTOR CIRCUITS.............................153
P0508 - IAC MOTOR SENSE CIRCUIT LOW................................156
P0509 - IAC MOTOR SENSE CIRCUIT HIGH...............................159
P0700-EATX CONTROLLER DTC PRESENT................................161
P0703-BRAKE SWITCH SENSE CIRCUIT..................................162
P0740-TORQ CONV CLU, NO RPM DROP AT LOCKUP (3SP AUTO TRANS).....165
P0743-TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CIRCUITS
(3SP AUTO TRANS)....................................................168
P0833-CLUTCH RELEASED SWITCH CIRCUIT.............................171
P1192-INLET AIR TEMP SENSOR VOLTAGE LOW...........................174
P1193-INLET AIR TEMP SENSOR VOLTAGE HIGH..........................176
P1195-1/1 O2 SENSOR SLOW DURING CATALYST MONITOR................178
P1281-ENGINE IS COLD TOO LONG......................................180
P1282-FUEL PUMP RELAY CONTROL CIRCUIT.............................181
P1294-TARGET IDLE NOT REACHED (2.4L)................................184
P1294-TARGET IDLE NOT REACHED (3.3L/3.8L)............................187
P1297-NO CHANGE IN MAP FROM START TO RUN.........................189
P1299-VACUUM LEAK FOUND (IAC FULLY SEATED)........................193
P1388-AUTO SHUTDOWN RELAY CONTROL CIRCUIT.......................195
P1389-NO ASD RELAY OUTPUT VOLTAGE AT PCM.........................198
P1391-INTERMITTENT LOSS OF CMP OR CKP.............................201
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT.........................205
P1486-EVAP LEAK MONITOR PINCHED HOSE FOUND......................207
P1491-RAD FAN CONTROL RELAY CIRCUIT...............................210
P1494-LEAK DETECT PUMP SW OR MECHANICAL FAULT...................214
P1495-LEAK DETECTION PUMP SOLENOID CIRCUIT.......................216
P1496-5 VOLT SUPPLY, OUTPUT TOO LOW...............................218
P1602-PCM NOT PROGRAMMED........................................221
P1899-P/N SWITCH STUCK IN PARK OR IN GEAR (3SP AUTO TRANS)........222
P1899-P/N SWITCH STUCK IN PARK OR IN GEAR (4SP AUTO TRNAS)........224
*CHECKING ECT SENSOR..............................................226
*CHECKING FUEL DELIVERY............................................227
*CHECKING IAC MOTOR (2.4L)..........................................231
*CHECKING IAT SENSOR...............................................232
iii

TABLE OF CONTENTS - Continued
AMBIENT TEMPERATURE SENSOR - BLACK 2 WAY........................291
AMBIENT TEMPERATURE SENSOR (SENSOR SIDE)-2WAY................292
BRAKE LAMP SWITCH - BLACK 6 WAY...................................292
BRAKE TRANSMISSION SHIFT INTERLOCK SOLENOID - BLACK 2 WAY.......292
CAMSHAFT POSITION SENSOR - BLACK 3 WAY...........................292
CLOCKSPRING C1 - WHITE 6 WAY.......................................292
CRANKSHAFT POSITION SENSOR - BLACK 3 WAY.........................293
DATA LINK CONNECTOR - WHITE 16 WAY................................293
DIAGNOSTIC JUNCTION PORT - BLACK 16 WAY...........................293
EGR SOLENOID - GRAY 2 WAY..........................................294
ENGINE COOLANT TEMPERATURE SENSOR - BLACK 2 WAY................294
ENGINE OIL PRESSURE SWITCH - LT. GREEN 2 WAY......................294
EVAP/PURGE SOLENOID - BLACK 2 WAY.................................294
FUEL INJECTOR NO. 1 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 2 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 3 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 4 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 5 (3.3L/3.8L) - BLACK 2 WAY..........................296
FUEL INJECTOR NO. 6 (3.3L/3.8L) - BLACK 2 WAY..........................296
FUEL TANK MODULE - LT. GRAY 4 WAY...................................296
GENERATOR - BLACK 2 WAY...........................................296
GENERATOR (GENERATOR SIDE).......................................297
MANIFOLD ABSOLUTE PRESSURE SENSOR - BLACK 3 WAY................297
OXYGEN SENSOR 1/1 UPSTREAM - BLACK 4 WAY.........................297
OXYGEN SENSOR 1/2 DOWNSTREAM - BLACK 4 WAY.....................297
FUSES (IPM)..........................................................299
A/C COMPRESSOR CLUTCH RELAY......................................299
ACCESSORY RELAY...................................................299
AUTOMATIC SHUTDOWN RELAY........................................300
ENGINE STARTER MOTOR RELAY.......................................300
FUEL PUMP RELAY....................................................300
POSITIVE TEMPERATURE COEFFICIENTS................................300
TRANSMISSION SAFETY SHUTDOWN RELAY.............................300
POWERTRAIN CONTROL MODULE C1 - GRAY/BLACK 40 WAY...............301
POWERTRAIN CONTROL MODULE C2 - GRAY/GRAY 40 WAY................302
10.0 SCHEMATIC DIAGRAMS................................................303
10.12001 RG 2.4L....................................................303
10.22001 RG 3.3L/3.8L................................................304
11.0 CHARTS AND GRAPHS................................................305
11.1SPECIFICATION..................................................305
v

3.2.3 OTHER CONTROLS
CHARGING SYSTEM
The charging system is turned on when the
engine is started and ASD relay energized. When
the ASD relay is on, ASD output voltage is supplied
to the ASD sense circuit at the PCM. This voltage is
connected in some cases, through the PCM and
supplied to one of the generator field terminals
(Gen Source +). All others, the Gen field is con-
nected directly to the ASD output voltage. The
amount of current produced by the generator is
controlled by the Electronic Voltage Regulator
(EVR) circuitry, in the PCM. Battery temperature is
determined from IAT. This temperature along with
sensed line voltage, is used by the PCM to vary the
battery charging rate. This is done by cycling the
ground path to the other generator field terminal
(Gen field driver).
SPEED CONTROL SYSTEM
The PCM controls vehicle speed by operation of
the speed control servo vacuum and vent solenoids.
Energizing the vacuum solenoid applies vacuum to
the servo to increase throttle position. Operation of
the vent solenoid slowly releases the vacuum allow-
ing throttle position to decrease. A special dump
solenoid allows immediate release of throttle posi-
tion caused by braking, cruise control switch turned
off, shifting into neutral, excessive RPM (tires spin-
ning) or ignition off.
LEAK DETECTION PUMP SYSTEM (IF EQUIPPED)
The leak detection pump is a device that pressur-
izes the evaporative system to determine if there
are any leaks. When certain conditions are met, the
PCM will activate the pump and start counting
pump strokes. If the pump stops within a calibrated
number of strokes, the system is determined to be
normal. If the pump does not stop or stops too soon,
a DTC will be set.
3.2.4 PCM OPERATING MODES
As input signals to the PCM change, the PCM
adjusts its response to output devices. For example,
the PCM must calculate a different injector pulse
width and ignition timing for idle than it does for
wide open throttle. There are several different
modes of operation that determine how the PCM
responds to the various input signals.
There are two types of engine control operation:
open loopandclosed loop.
Inopen loopoperation, the PCM receives input
signals and responds according to preset program-
ming. Inputs from the heated oxygen sensors are
not monitored.Inclosed loopoperation, the PCM monitors the
inputs from the heated oxygen sensors. This input
indicates to the PCM whether or not the calculated
injector pulse width results in the ideal air-fuel
ratio of 14.7 parts air to 1 part fuel. By monitoring
the exhaust oxygen content through the oxygen
sensor, the PCM can fine tune injector pulse width.
Fine tuning injector pulse width allows the PCM to
achieve the lowest emission levels while maintain-
ing optimum fuel economy.
The engine start-up (crank), engine warm-up,
and wide open throttle modes are open loop modes.
Under most operating conditions, closed loop modes
occur with the engine at operating temperature.
IGNITION SWITCH ON (ENGINE OFF) MODE
When the ignition switch activates the fuel injec-
tion system, the following actions occur:
1. The PCM determines atmospheric air pressure
from the MAP sensor input to determine basic
fuel strategy.
2. The PCM monitors the engine coolant tempera-
ture sensor and throttle position sensor input.
The PCM modifies fuel strategy based on this
input.
When the key is in the on position and the engine
is not running (zero rpm), the auto shutdown relay
and fuel pump relay are not energized. Therefore,
voltage is not supplied to the fuel pump, ignition
coil, and fuel injectors.
Engine Start-up ModeÐ This is an open loop
mode. The following actions occur when the starter
motor is engaged:
1. The auto shutdown and fuel pump relays are
energized. If the PCM does not receive the cam-
shaft and crankshaft signal within approxi-
mately one second, these relays are de-
energized.
2. The PCM energizes all fuel injectors until it
determines crankshaft position from the cam-
shaft and crankshaft signals. The PCM deter-
mines crankshaft position within one engine
revolution. After the camshaft position has been
determined, the PCM energizes the fuel injectors
in sequence. The PCM adjusts the injector pulse
width and synchronizes the fuel injectors by
controlling the fuel injectors' ground paths.
3. Once the engine idles within 64 rpm of its target
engine speed, the PCM compares the current
MAP sensor value with the value received dur-
ing the ignition switch on (zero rpm) mode. A
diagnostic trouble code is written to PCM mem-
ory if a minimum difference between the two
values is not found.
4
GENERAL INFORMATION

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

When testing voltage or continuity at any control
module, use the terminal side (not the wire end) of
the connector. Do not probe a wire through the
insulation; this will damage it and eventually cause
it to fail because of corrosion.
Be careful when performing electrical tests so as
to prevent accidental shorting of terminals. Such
mistakes can damage fuses or components. Also, a
second DTC could be set, making diagnosis of the
original problem more difficult.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box) scan tool
Evaporative System Diagnostic Kit #6917
fuel filler adapter #8382
fuel pressure adapter (C-6631) or #6539
fuel pressure kit (C-4799-B) or #5069
fuel release hose (C-4799-1)
Min Air flow fitting #6714
jumper wires
ohmmeter
oscilloscope
vacuum gauge
voltmeter
12 volt test light minimum 25 ohms resistance
with probe #6801
CAUTION: A 12 VOLT TEST LIGHT SHOULD
NOT BE USED FOR THE FOLLOWING
CIRCUITS, DAMAGE TO THE POWERTRAIN
CONTROLLER WILL OCCUR.
²5 Volt Supply
²8 Volt Supply
²J1850 PCI Bus
²CCD Bus
²CKP Sensor Signal
²CMP Sensor Signal
²Vehicle Speed Sensor Signal
²O2 Sensor Signal
6.0 GLOSSARY OF TERMS
ABSanti-lock brake system
backfire,
popbackfuel ignites in either the intake or
the exhaust system
CKPcrank position sensor
CMPcamshaft position sensorcuts out,
missesa steady pulsation or the inability of
the engine to maintain a consistent
rpm
DLCdata link connector (previously
called engine diagnostic connector)
detona-
tion,
spark
knocka mild to severe ping, especially un-
der loaded engine conditions
ECTengine coolant temperature sensor
EGRexhaust gas recirculation valve
genera-
torpreviously called alternator
hard
startThe engine takes longer than usual
to start, even though it is able to
crank normally.
hesita-
tion, sag,
stumbleThere is a momentary lack of re-
sponse when the throttle is opened.
This can occur at all vehicle speeds.
If it is severe enough, the engine
may stall.
IATintake air temperature sensor
IACidle air control motor
JTECCombined engine and transmission
control module
lack of
power,
sluggishThe engine has less than expected
power, with little or no increase in
vehicle speed when the throttle is
opened.
LDPleak detection pump
MAPmanifold absolute pressure sensor
MILmalfunction indicator lamp
MTVmanifold tuning valve
O2Soxygen sensor
PCIprogrammable communication inter-
face
PCMpowertrain control module
PCVpositive crankcase ventilation
PEPperipheral expansion port
poor fuel
economyThere is significantly less fuel mile-
age than other vehicles of the same
design ad configuration
12
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
10 Turn the ignition on.
Disconnect the O2 Sensor harness connector.
With the DRBIIIt, monitor the O2 Sensor voltage.
Is the O2 Sensor voltage between 0.40 to 0.60 volts?All
Ye s®Replace the O2 Sensor
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 11
11 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the O2 Sensor Signal circuit in the PCM harness connector
to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the O2 Sensor Signal for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 12
12 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
13 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 5/16 fuel line adapter tool #6539 between disconnected fuel line and
the fuel pump module.
Attach a fuel pressure test gauge to the T fitting 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 (58.2 psi +/- 5 psi).
Is the fuel pressure within specification?All
Ye s®Repair or replace fuel supply line as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 14
Caution: Stop All Actuations.
14 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 - 5.
No®Go To 15
93
DRIVEABILITY - GAS
P0171-1/1 FUEL SYSTEM LEAN ÐContinued

TEST ACTION APPLICABILITY
15 If there are no possible causes remaining, view repair. All
Repair
Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
16NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
94
DRIVEABILITY - GAS
P0171-1/1 FUEL SYSTEM LEAN ÐContinued

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