dash JEEP WRANGLER 1994 Owners Manual

ACCELERATOR PEDAL AND THROTTLE CABLE
GENERAL INFORMATION
The accelerator pedal is connected to the throttle body
linkage by the throttle cable. The cable is protected by a
plastic sheathing and is connected to the throttle body
linkage by a ball socket. It is connected to the upper part
of the accelerator pedal arm by a plastic retainer (clip)
(Fig. 10). This retainer (clip) snaps into the top of the ac-
celerator pedal arm. Retainer tabs (built into the cable
sheathing) (Fig. 10) fasten the cable to the dash panel.
Dual throttle return springs (attached to the throt-
tle shaft) are used to close the throttle.
CAUTION: Never attempt to remove or alter these springs.
ACCELERATOR PEDAL
CAUTION: Be careful not to damage or kink the ca-
ble core wire (within the cable sheathing) while ser-
vicing the accelerator pedal or throttle cable.
REMOVAL
(1) From inside the vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of accelerator pedal arm (Fig.
10). Plastic cable retainer (clip) snaps into pedal arm.
(2) Remove accelerator pedal mounting bracket
nuts. Remove accelerator pedal assembly.
INSTALLATION
(1) Place accelerator pedal assembly over studs
protruding from floor pan. Tighten mounting nuts to
5Nzm (36 in. lbs.) torque.
(2) Slide throttle cable into opening in top of pedalarm. Push plastic cable retainer (clip) into accelera-
tor pedal arm opening until it snaps into place.
(3) Before starting engine, operate accelerator
pedal to check for any binding.
THROTTLE CABLE
REMOVAL
(1) From inside the vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of accelerator pedal arm (Fig.
10). Plastic cable retainer (clip) snaps into pedal arm.
(2) Remove the cable core wire at pedal arm.
(3) From inside the vehicle, pinch both sides of the
cable housing retainer tabs (Fig. 10) at the dash
panel. Remove cable housing from dash panel and
pull into the engine compartment.
(4) Remove cable from clip on the engine cylinder
head (valve) cover.
(5) Remove the throttle cable ball end socket at
throttle body linkage (snaps off) (Fig. 11).
(6) Remove throttle cable from throttle body mount-
ing bracket by compressing retainer tabs and pushing
cable through hole in bracket. Remove throttle cable
from vehicle.
INSTALLATION
(1) Slide throttle cable through hole in throttle body
bracket until retainer tabs lock into bracket. Connect
cable ball end to throttle body linkage ball (snaps on).
(2) Snap cable into clip on the engine cylinder
head (valve) cover.
(3) Push other end of cable through opening in
dash panel until retaining tabs lock into panel.
(4) From inside drivers compartment, slide throttle
cable core wire into opening in top of accelerator
pedal arm. Push cable retainer (clip) into pedal arm
opening until it snaps in place.
(5) Before starting engine, operate accelerator
pedal to check for any binding.
Fig. 10 Accelerator Pedal MountingÐTypicalFig. 11 Throttle (Accelerator) CableÐTypical
14 - 16 FUEL SYSTEMJ

Refer to Group 8D, Ignition System for more crank-
shaft position sensor information.
The engine will not operate if the PCM does not re-
ceive a crankshaft position sensor input.
ENGINE COOLANT TEMPERATURE SENSORÐPCM
INPUT
The coolant temperature sensor is installed in the
thermostat housing (Fig. 10) and protrudes into the
water jacket. The sensor provides an input voltage to
the powertrain control module (PCM) relating cool-
ant temperature. The PCM uses this input along
with inputs from other sensors to determine injector
pulse width and ignition timing. As coolant temper-
ature varies, the coolant temperature sensor's resis-
tance changes. The change in resistance results in a
different input voltage to the PCM.
When the engine is cold, the PCM will operate in
Open Loop cycle. It will demand slightly richer air-
fuel mixtures and higher idle speeds. This is done
until normal operating temperatures are reached.
Refer to Open Loop/Closed Loop Modes of Opera-
tion in this section of the group for more information.
EXTENDED IDLE SWITCHÐPCM INPUT
OPTIONAL POLICE PACKAGE ONLY
The extended idle switch is used to raise the en-
gine idle speed to approximately 1000 rpm. This is
when the shifter is in either the Park or Neutral po-
sition. A rocker-type 2-wire switch (extended idle
switch) is mounted to the instrument panel. This
switch will supply a ground circuit to the powertrain
control module (PCM).The switch is available
only with 4.0L engine when supplied with the
optional police package.
For testing and diagnosis of this switch and its cir-
cuit, refer to the MFI SystemÐGeneral Diagnosis
section of this group.
IGNITION CIRCUIT SENSEÐPCM INPUT
The ignition circuit sense input tells the powertrain
control module (PCM) the ignition switch has ener-
gized the ignition circuit. Refer to the wiring dia-
grams for circuit information.
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐPCM INPUT
The MAP sensor reacts to absolute pressure in the
intake manifold. It provides an input voltage to the
powertrain control module (PCM). As engine load
changes, manifold pressure varies. The change in
manifold pressure causes MAP sensor voltage to
change. The change in MAP sensor voltage results in
a different input voltage to the PCM. The input volt-
age level supplies the PCM with information about
ambient barometric pressure during engine start-up
(cranking) and engine load while the engine is run-
ning. The PCM uses this input along with inputs
from other sensors to adjust air-fuel mixture.
The MAP sensor is mounted on the dash panel.
The sensor is connected to the throttle body with a
vacuum hose and to the PCM electrically.
Fig. 8 Sensor LocationÐ4.0L Engine
Fig. 9 Sensor LocationÐ2.5L Engine
Fig. 10 Coolant Temperature SensorÐTypical
JFUEL SYSTEM 14 - 21

(10) Inspect fuel tube quick-connect fitting-to-fuel
rail connections (Fig. 15).
(11) Verify that hose connections to all ports of
vacuum fittings on intake manifold are tight and not
leaking.
(12) Inspect accelerator cable, transmission throt-
tle cable (if equipped) and cruise control cable con-
nections (if equipped). Check their connections to the
throttle arm of throttle body for any binding or re-
strictions (Fig. 16).
(13) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit-
ting on intake manifold. Also check connection to
brake vacuum booster (Fig. 17).
(14) On XJ models equipped with 4.0L engine and
A/C, verify that auxiliary cooling fan wire connector
is firmly connected to harness (Fig. 18).
(15) Inspect the air cleaner inlet and air filter ele-
ment for restrictions.
(16) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions.(17) Verify that intake manifold air temperature
sensor wire connector is firmly connected to harness
connector (Figs. 19 or 20).
(18) Inspect engine ground strap connections at
dash panel and rear cylinder head bolt (Fig. 21).
(19) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 22). Verify that
vacuum hose is firmly connected to MAP sensor and
to the intake manifold.
(20) Verify that fuel injector wire harness connec-
tors are firmly connected to the fuel injectors in the
correct order. Each harness connector is tagged with
the number of its corresponding fuel injector (Fig.
23).
Fig. 15 Fuel Supply TubeÐTypical
Fig. 16 Throttle Body CablesÐTypical
Fig. 17 Brake Vacuum Booster HoseÐTypical
Fig. 18 Auxiliary Cooling Fan ConnectorÐXJ with
4.0L Engine
JFUEL SYSTEM 14 - 35

REMOVAL
(1) Disconnect the electrical connector from the
IAC motor.
(2) Remove IAC motor torx head mounting bolts.
(3) Remove IAC motor.
INSTALLATION
(1) Install IAC motor into throttle body and
tighten retaining bolts.
(2) Connect electrical connector to IAC motor.
IGNITION COIL
Refer to Group 8D, Ignition Systems for removal/
installation procedures.
INTAKE MANIFOLD
Refer to Group 11, Exhaust System and Intake
Manifold for removal/installation procedures.
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
The MAP sensor is located on the dash panel near
the rear of the engine cylinder head (valve) cover
(Fig. 9).
REMOVAL
(1) Disconnect the MAP sensor electrical connector
(Fig. 9).
(2) Disconnect the MAP sensor vacuum supply
hose (Fig. 9).
(3) Remove the MAP sensor mounting bolts and
remove MAP sensor.
INSTALLATION
(1) Install MAP sensor to dash panel and secure
with mounting bolts.
(2) Install the MAP sensor vacuum supply hose.
(3) Connect the MAP sensor electrical connector.
OXYGEN (O2S) SENSOR
The O2S sensor is installed in the exhaust down
pipe just below the exhaust manifold flange (Fig. 10).
REMOVAL
WARNING: THE EXHAUST MANIFOLD BECOMES
VERY HOT DURING ENGINE OPERATION. ALLOW
ENGINE TO COOL BEFORE REMOVING OXYGEN
SENSOR.
(1) Raise and support the vehicle.
(2) Separate the electrical connectors.
(3) Remove the O2S sensor from the exhaust man-
ifold. Snap-On oxygen sensor wrench (number YA
8875) may be used for removal and installation.
INSTALLATION
Threads of new factory oxygen sensors are coated
with anti-seize compound to aid in removal.
(1) Install the O2S sensor into the exhaust mani-
fold and tighten to 30 Nzm (22 ft. lbs.) torque.
(2) Connect the O2S sensor wire connector to the
main harness.
Fig. 8 Idle Air Control
MotorÐRemoval/InstallationÐTypical
Fig. 9 MAP SensorÐTypical
Fig. 10 Oxygen SensorÐTypical
JFUEL SYSTEM 14 - 57

Fig. 23 Cowl Seal and Retainers
Fig. 24 Dash Panel Insulator Panel
Fig. 25 Wiper Locations On Windshield
JBODY COMPONENTSÐXJ VEHICLES 23 - 11

ACCELERATOR PEDAL AND THROTTLE CABLE
GENERAL INFORMATION
The accelerator pedal is connected to the throttle body
linkage by the throttle cable. The cable is protected by a
plastic sheathing and is connected to the throttle body
linkage by a ball socket. It is connected to the upper part
of the accelerator pedal arm by a plastic retainer (clip)
(Fig. 10). This retainer (clip) snaps into the top of the ac-
celerator pedal arm. Retainer tabs (built into the cable
sheathing) (Fig. 10) fasten the cable to the dash panel.
Dual throttle return springs (attached to the throt-
tle shaft) are used to close the throttle.
CAUTION: Never attempt to remove or alter these springs.
ACCELERATOR PEDAL
CAUTION: Be careful not to damage or kink the ca-
ble core wire (within the cable sheathing) while ser-
vicing the accelerator pedal or throttle cable.
REMOVAL
(1) From inside the vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of accelerator pedal arm (Fig.
10). Plastic cable retainer (clip) snaps into pedal arm.
(2) Remove accelerator pedal mounting bracket
nuts. Remove accelerator pedal assembly.
INSTALLATION
(1) Place accelerator pedal assembly over studs
protruding from floor pan. Tighten mounting nuts to
5Nzm (36 in. lbs.) torque.
(2) Slide throttle cable into opening in top of pedalarm. Push plastic cable retainer (clip) into accelera-
tor pedal arm opening until it snaps into place.
(3) Before starting engine, operate accelerator
pedal to check for any binding.
THROTTLE CABLE
REMOVAL
(1) From inside the vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of accelerator pedal arm (Fig.
10). Plastic cable retainer (clip) snaps into pedal arm.
(2) Remove the cable core wire at pedal arm.
(3) From inside the vehicle, pinch both sides of the
cable housing retainer tabs (Fig. 10) at the dash
panel. Remove cable housing from dash panel and
pull into the engine compartment.
(4) Remove cable from clip on the engine cylinder
head (valve) cover.
(5) Remove the throttle cable ball end socket at
throttle body linkage (snaps off) (Fig. 11).
(6) Remove throttle cable from throttle body mount-
ing bracket by compressing retainer tabs and pushing
cable through hole in bracket. Remove throttle cable
from vehicle.
INSTALLATION
(1) Slide throttle cable through hole in throttle body
bracket until retainer tabs lock into bracket. Connect
cable ball end to throttle body linkage ball (snaps on).
(2) Snap cable into clip on the engine cylinder
head (valve) cover.
(3) Push other end of cable through opening in
dash panel until retaining tabs lock into panel.
(4) From inside drivers compartment, slide throttle
cable core wire into opening in top of accelerator
pedal arm. Push cable retainer (clip) into pedal arm
opening until it snaps in place.
(5) Before starting engine, operate accelerator
pedal to check for any binding.
Fig. 10 Accelerator Pedal MountingÐTypicalFig. 11 Throttle (Accelerator) CableÐTypical
14 - 16 FUEL SYSTEMJ

Refer to Group 8D, Ignition System for more crank-
shaft position sensor information.
The engine will not operate if the PCM does not re-
ceive a crankshaft position sensor input.
ENGINE COOLANT TEMPERATURE SENSORÐPCM
INPUT
The coolant temperature sensor is installed in the
thermostat housing (Fig. 10) and protrudes into the
water jacket. The sensor provides an input voltage to
the powertrain control module (PCM) relating cool-
ant temperature. The PCM uses this input along
with inputs from other sensors to determine injector
pulse width and ignition timing. As coolant temper-
ature varies, the coolant temperature sensor's resis-
tance changes. The change in resistance results in a
different input voltage to the PCM.
When the engine is cold, the PCM will operate in
Open Loop cycle. It will demand slightly richer air-
fuel mixtures and higher idle speeds. This is done
until normal operating temperatures are reached.
Refer to Open Loop/Closed Loop Modes of Opera-
tion in this section of the group for more information.
EXTENDED IDLE SWITCHÐPCM INPUT
OPTIONAL POLICE PACKAGE ONLY
The extended idle switch is used to raise the en-
gine idle speed to approximately 1000 rpm. This is
when the shifter is in either the Park or Neutral po-
sition. A rocker-type 2-wire switch (extended idle
switch) is mounted to the instrument panel. This
switch will supply a ground circuit to the powertrain
control module (PCM).The switch is available
only with 4.0L engine when supplied with the
optional police package.
For testing and diagnosis of this switch and its cir-
cuit, refer to the MFI SystemÐGeneral Diagnosis
section of this group.
IGNITION CIRCUIT SENSEÐPCM INPUT
The ignition circuit sense input tells the powertrain
control module (PCM) the ignition switch has ener-
gized the ignition circuit. Refer to the wiring dia-
grams for circuit information.
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐPCM INPUT
The MAP sensor reacts to absolute pressure in the
intake manifold. It provides an input voltage to the
powertrain control module (PCM). As engine load
changes, manifold pressure varies. The change in
manifold pressure causes MAP sensor voltage to
change. The change in MAP sensor voltage results in
a different input voltage to the PCM. The input volt-
age level supplies the PCM with information about
ambient barometric pressure during engine start-up
(cranking) and engine load while the engine is run-
ning. The PCM uses this input along with inputs
from other sensors to adjust air-fuel mixture.
The MAP sensor is mounted on the dash panel.
The sensor is connected to the throttle body with a
vacuum hose and to the PCM electrically.
Fig. 8 Sensor LocationÐ4.0L Engine
Fig. 9 Sensor LocationÐ2.5L Engine
Fig. 10 Coolant Temperature SensorÐTypical
JFUEL SYSTEM 14 - 21

(10) Inspect fuel tube quick-connect fitting-to-fuel
rail connections (Fig. 15).
(11) Verify that hose connections to all ports of
vacuum fittings on intake manifold are tight and not
leaking.
(12) Inspect accelerator cable, transmission throt-
tle cable (if equipped) and cruise control cable con-
nections (if equipped). Check their connections to the
throttle arm of throttle body for any binding or re-
strictions (Fig. 16).
(13) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit-
ting on intake manifold. Also check connection to
brake vacuum booster (Fig. 17).
(14) On XJ models equipped with 4.0L engine and
A/C, verify that auxiliary cooling fan wire connector
is firmly connected to harness (Fig. 18).
(15) Inspect the air cleaner inlet and air filter ele-
ment for restrictions.
(16) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions.(17) Verify that intake manifold air temperature
sensor wire connector is firmly connected to harness
connector (Figs. 19 or 20).
(18) Inspect engine ground strap connections at
dash panel and rear cylinder head bolt (Fig. 21).
(19) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 22). Verify that
vacuum hose is firmly connected to MAP sensor and
to the intake manifold.
(20) Verify that fuel injector wire harness connec-
tors are firmly connected to the fuel injectors in the
correct order. Each harness connector is tagged with
the number of its corresponding fuel injector (Fig.
23).
Fig. 15 Fuel Supply TubeÐTypical
Fig. 16 Throttle Body CablesÐTypical
Fig. 17 Brake Vacuum Booster HoseÐTypical
Fig. 18 Auxiliary Cooling Fan ConnectorÐXJ with
4.0L Engine
JFUEL SYSTEM 14 - 35

REMOVAL
(1) Disconnect the electrical connector from the
IAC motor.
(2) Remove IAC motor torx head mounting bolts.
(3) Remove IAC motor.
INSTALLATION
(1) Install IAC motor into throttle body and
tighten retaining bolts.
(2) Connect electrical connector to IAC motor.
IGNITION COIL
Refer to Group 8D, Ignition Systems for removal/
installation procedures.
INTAKE MANIFOLD
Refer to Group 11, Exhaust System and Intake
Manifold for removal/installation procedures.
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
The MAP sensor is located on the dash panel near
the rear of the engine cylinder head (valve) cover
(Fig. 9).
REMOVAL
(1) Disconnect the MAP sensor electrical connector
(Fig. 9).
(2) Disconnect the MAP sensor vacuum supply
hose (Fig. 9).
(3) Remove the MAP sensor mounting bolts and
remove MAP sensor.
INSTALLATION
(1) Install MAP sensor to dash panel and secure
with mounting bolts.
(2) Install the MAP sensor vacuum supply hose.
(3) Connect the MAP sensor electrical connector.
OXYGEN (O2S) SENSOR
The O2S sensor is installed in the exhaust down
pipe just below the exhaust manifold flange (Fig. 10).
REMOVAL
WARNING: THE EXHAUST MANIFOLD BECOMES
VERY HOT DURING ENGINE OPERATION. ALLOW
ENGINE TO COOL BEFORE REMOVING OXYGEN
SENSOR.
(1) Raise and support the vehicle.
(2) Separate the electrical connectors.
(3) Remove the O2S sensor from the exhaust man-
ifold. Snap-On oxygen sensor wrench (number YA
8875) may be used for removal and installation.
INSTALLATION
Threads of new factory oxygen sensors are coated
with anti-seize compound to aid in removal.
(1) Install the O2S sensor into the exhaust mani-
fold and tighten to 30 Nzm (22 ft. lbs.) torque.
(2) Connect the O2S sensor wire connector to the
main harness.
Fig. 8 Idle Air Control
MotorÐRemoval/InstallationÐTypical
Fig. 9 MAP SensorÐTypical
Fig. 10 Oxygen SensorÐTypical
JFUEL SYSTEM 14 - 57

Fig. 9 Booster Attachment At Dash PanelÐYJ
Shown
JABS COMPONENT SERVICE 5 - 51