The PCM adjusts injector pulse width based on pre-
programmed (fixed) values and inputs from other
sensors.
NGC Controller - Has a common ground for the
heater in the O2S. 12 volts is supplied to the heater
in the O2S by the NGC controller. Both the upstream
and downstream O2 sensors for NGC are pulse width
modulation (PWM).NOTE: When replacing an O2
Sensor, the PCM RAM memory must be cleared,
either by disconnecting the PCM C-1 connector or
momentarily disconnecting the Battery negative ter-
minal. The NGC learns the characteristics of each O2
heater element and these old values should be
cleared when installing a new O2 sensor. The cus-
tomer may experience driveability issues if this is not
performed.
UPSTREAM OXYGEN SENSOR
The input from the upstream heated oxygen sensor
tells the PCM the oxygen content of the exhaust gas.
Based on this input, the PCM fine tunes the air-fuel
ratio by adjusting injector pulse width.
The sensor input switches from 2.5 to 3.5 volt,
depending upon the oxygen content of the exhaust
gas in the exhaust manifold. When a large amount of
oxygen is present (caused by a lean air-fuel mixture),
the sensor produces voltage as low as 2.5 volt. When
there is a lesser amount of oxygen present (rich air-
fuel mixture) the sensor produces a voltage as high
as 3.5 volt. By monitoring the oxygen content and
converting it to electrical voltage, the sensor acts as
a rich-lean switch.
The heating element in the sensor provides heat to
the sensor ceramic element. Heating the sensor
allows the system to enter into closed loop operation
sooner. Also, it allows the system to remain in closed
loop operation during periods of extended idle.
In Closed Loop, the PCM adjusts injector pulse
width based on the upstream heated oxygen sensor
input along with other inputs. In Open Loop, the
PCM adjusts injector pulse width based on prepro-
grammed (fixed) values and inputs from other sen-
sors.
DOWNSTREAM OXYGEN SENSOR
The downstream heated oxygen sensor input is
used to detect catalytic convertor deterioration. As
the convertor deteriorates, the input from the down-
stream sensor begins to match the upstream sensor
input except for a slight time delay. By comparing
the downstream heated oxygen sensor input to the
input from the upstream sensor, the PCM calculates
catalytic convertor efficiency. Also used to establish
the upstream O2 goal voltage (switching point).
REMOVAL
REMOVAL - UPSTREAM 1/1 - 2.4L
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Disconnect the electrical connector (Fig. 23).
(4) Use a socket such as the Snap-OntYA8875 or
equivalent to remove the sensor
(5) When the sensor is removed, the threads must
be cleaned with an 18 mm X 1.5 + 6E tap. If using
the original sensor, coat the threads with Loctite
771±64 anti-seize compound or equivalent.
REMOVAL - UPSTREAM 1/1 - 3.3/3.8L
(1) Remove battery, refer to the Battery section for
more information.
(2) Remove the battery tray, refer to the Battery
section for more information.
(3) Disconnect the speed control vacuum harness
from servo.
(4) Disconnect the electrical connector from servo.
(5) Remove the speed control servo and bracket
and reposition.
(6) Use a socket such as the Snap-OntYA8875 or
equivalent to remove the sensor (Fig. 25).
(7) When the sensor is removed, the threads must
be cleaned with an 18 mm X 1.5 + 6E tap. If using
the original sensor, coat the threads with Loctite
771±64 anti-seize compound or equivalent.
Fig. 25 O2 SENSOR 1/1
RSFUEL INJECTION14-33
O2 SENSOR (Continued)
REMOVAL - DOWNSTREAM 1/2 - 2.4/3.3/3.8L
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Disconnect the electrical connector (Fig. 26).
(4) Use a socket such as the Snap-OntYA8875 or
equivalent to remove the sensor (Fig. 27).
(5) When the sensor is removed, the threads must
be cleaned with an 18 mm X 1.5 + 6E tap. If using
the original sensor, coat the threads with Loctite
771±64 anti-seize compound or equivalent.
INSTALLATION
INSTALLATION - UPSTREAM 1/1 - 2.4L
The engines uses two heated oxygen sensors.
(1) After removing the sensor, the exhaust mani-
fold threads must be cleaned with an 18 mm X 1.5 +
6E tap. If reusing the original sensor, coat the sensor
threads with an anti-seize compound such as Loctite
771- 64 or equivalent. New sensors have compound
on the threads and do not require an additional coat-
ing.
(2) Install sensor and tighten to 27 N´m (20 ft.
lbs.) (Fig. 23).
(3) Connect the electrical connector for the O2 sen-
sor and install onto bracket.
(4) Lower vehicle.
(5) Connect the negative battery cable.
INSTALLATION - UPSTREAM 1/1 - 3.3/3.8L
The engines uses two heated oxygen sensors.
(1) After removing the sensor, the exhaust mani-
fold threads must be cleaned with an 18 mm X 1.5 +
6E tap. If reusing the original sensor, coat the sensor
threads with an anti-seize compound such as Loctite
771- 64 or equivalent. New sensors have compound
on the threads and do not require an additional coat-
ing.
(2) Install sensor and tighten to 27 N´m (20 ft.
lbs.).
(3) Connect the electrical connector for the O2 sen-
sor and install onto bracket.
(4) Connect the electrical connector for the speed
control servo.
(5) Install the speed control servo and bracket
refer to the Speed Control Servo for more informa-
tion.
(6) Connect the speed control vacuum harness to
servo.
(7) Install the battery tray, refer to the Battery
section for more information.
(8) Install battery, refer to the Battery section for
more information.
INSTALLATION DOWNSTREAM 2/1 -
2.4/3.3/3.8L
The O2S is located on the side of the catalytic con-
verter.
Threads of new oxygen sensors are factory coated
with anti-seize compound to aid in removal.DO
NOT add any additional anti-seize compound to
the threads of a new oxygen sensor.
(1) Install sensor and tighten to 27 N´m (20 ft.
lbs.).
(2) Connect the electrical connector.
(3) Lower vehicle.
(4) Install the negative battery cable.
Fig. 26 Downstream Oxygen Sensor (1/2)
1 - OXYGEN SENSOR CONNECTOR
2 - CATALYTIC CONVERTER
3 - DOWNSTREAM OXYGEN SENSOR
4 - ENGINE HARNESS CONNECTOR
Fig. 27 DOWNSTREAM 2/1 O2 SENSOR
14 - 34 FUEL INJECTIONRS
O2 SENSOR (Continued)
THROTTLE BODY
DESCRIPTION
The throttle body is located on the intake manifold
(Fig. 28) or (Fig. 29). Fuel does not enter the intake
manifold through the throttle body. Fuel is sprayed
into the manifold by the fuel injectors.
OPERATION
Filtered air from the air cleaner enters the intake
manifold through the throttle body. The throttle bodycontains an air control passage controlled by an Idle
Air Control (IAC) motor. The air control passage is
used to supply air for idle conditions. A throttle valve
(plate) is used to supply air for above idle conditions.
Certain sensors are attached to the throttle body.
The accelerator pedal cable, speed control cable are
connected to the throttle body cam.
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the PCM.
REMOVAL
(1) Disconnect negative cable from battery cable.
(2) Remove air inlet to throttle body hose clamp.
(3) Remove throttle and the speed control (if
equipped) cables from lever and bracket.
(4) Disconnect electrical connectors from the idle
air control motor and throttle position sensor (TPS)
(Fig. 28) or (Fig. 29).
(5) Remove throttle body to intake manifold
attaching bolts.
(6) Remove throttle body and gasket.
INSTALLATION
(1) Install a new gasket, if required.
(2) Install throttle body.
(3) Tighten throttle body mounting bolts. The 2.4L
to 28.2 N´m (250 50 in. lbs.) torque, The 3.3/3.8L to
11.6 N´m (105 20 in. lbs.) torque.
(4) Connect electrical connectors to the idle air
control motor and throttle position sensor (TPS) (Fig.
28) or (Fig. 29).
(5) Install air inlet to throttle body hose clamp and
tighten.
(6) Connect negative cable to battery cable.
THROTTLE CONTROL CABLE
REMOVAL
(1) Working from the engine compartment, hold
the throttle body throttle lever in the wide open posi-
tion.
(2) Remove the throttle cable from the throttle
body cam.
(3) From inside the vehicle, hold up the pedal and
remove the cable retainer and throttle cable from the
upper end of the pedal shaft.
(4) Remove retainer clip from throttle cable and
grommet at dash panel.
(5) From the engine compartment, pull the throttle
cable and gromment out of the dash panel.
(6) Remove the throttle cable from throttle bracket
by carefully compressing both retaining ears simulta-
Fig. 28 IAC VALVE 2.4L
1 - Idle Air Control Valve
2 - Throttle Position Sensor
Fig. 29 IAC VALVE LOCATION 3.3/3.8L
1 - Idle Air Control Valve
2 - Throttle Position Sensor
RSFUEL INJECTION14-35
neously then gently pull the throttle cable from
throttle bracket or if it is the slide snap design you
have to slide the locking tab out of the hole and then
slide the cable assembly out of the bracket.
INSTALLATION
(1) From the engine compartment, push the hous-
ing end fitting and grommet into the dash panel.In-
stall gromment into the dash panel.
(2) Install the cable housing (throttle body end)
into the cable mounting bracket on the engine.
(3) From inside the vehicle, hold up the pedal and
install throttle cable and cable retainer in the upper
end of the pedal shaft.
(4) At the dash panel, install the cable retainer
clip between the end of the throttle cable fitting and
grommet
(5) From the engine compartment, rotate the
throttle lever wide open and install the throttle
cable.
THROTTLE POSITION SENSOR
DESCRIPTION
The throttle position sensor mounts to the side of
the throttle body (Fig. 30) or (Fig. 31).The sensor
connects to the throttle blade shaft. The TPS is a
variable resistor that provides the Powertrain Con-
trol Module (PCM) with an input signal (voltage).
OPERATION
The signal represents throttle blade position. As
the position of the throttle blade changes, the resis-
tance of the TPS changes.
The PCM supplies approximately 5 volts to the
TPS. The TPS output voltage (input signal to the
powertrain control module) represents throttle blade
position. The TPS output voltage to the PCM varies
from approximately 0.6 volt at minimum throttle
opening (idle) to a maximum of 4.5 volts at wide open
throttle.
Along with inputs from other sensors, the PCM
uses the TPS input to determine current engine oper-
ating conditions. The PCM also adjusts fuel injector
pulse width and ignition timing based on these
inputs.
REMOVAL - 3.3/3.8L
(1) Disconnect the negative battery cable.
(2) Remove the electrical connector from the Inlet
Air Temperature sensor.
(3) Remove the air cleaner box lid. Remove hose
from throttle body.
(4) Disconnect the electrical connector at TPS.
(5) Disconnect the electrical connector at IAC.
(6) Remove the throttle and speed control cables
from throttle body.
(7) Remove 3 mounting bolts from throttle body.
(8) Remove throttle body.
(9) Disconnect the purge vacuum line from the
throttle body.
(10) Remove TPS from throttle body.
Fig. 30 Throttle Position SensorÐ2.4L Engine
1 - Idle Air Control Valve
2 - Throttle Position Sensor
Fig. 31 Throttle Position SensorÐ3.3/3.8L Engine
1 - Idle Air Control Valve
2 - Throttle Position Sensor
14 - 36 FUEL INJECTIONRS
THROTTLE CONTROL CABLE (Continued)
INSTALLATION - 3.3/3.8L
(1) Install TPS to throttle body.
(2) Disconnect the purge vacuum line from the
throttle body.
(3) Install throttle body.
(4) Install 3 mounting bolts from throttle body.
Tighten bolts.
(5) Install the throttle and speed control cables to
throttle body.(6) Connect the electrical connector at TPS.
(7) Connect the electrical connector at IAC.
(8) Install the air cleaner box lid. Install hose to
throttle body.
(9) Install the electrical connector to the Inlet Air
Temperature sensor.
(10) Connect the negative battery cable.
RSFUEL INJECTION14-37
THROTTLE POSITION SENSOR (Continued)
REMOVAL
REMOVAL - PUMP (2.4L ENGINE)
(1) Remove the (-) negative battery cable from the
battery and isolate cable.
(2) Remove the cap from the power steering fluid
reservoir.
(3) Using a siphon pump, remove as much power
steering fluid as possible from the power steering
fluid reservoir.
(4) Raise the vehicle on jack stands or centered on
a frame contact type hoist. See Hoisting in Lubrica-
tion and Maintenance.
(5) Disconnect the oxygen sensor wiring harness
from the vehicle wiring harness at the rear engine
mount bracket.
NOTE: The exhaust system needs to be removed
from the engine to allow for an area to remove the
power steering pump from the vehicle.
(6) Remove the four bolts and flag nuts securing
the catalytic converter from the exhaust manifold
(Fig. 3).
(7) Disconnect all the exhaust system isolators/
hangers from the brackets on the exhaust system (2
at the mufflers and 1 at the resonator) (Fig. 4).
(8) Remove the exhaust system by moving it as far
rearward, then lowering the front below the cross-
member and out of the vehicle.
(9) Remove the power steering fluid supply hose
from the fitting on the power steering pump. Drain
off excess power steering fluid from hose.(10) Move the heat sleeve on the power steering
return hose to expose the hose connection at the
pump (Fig. 5). Remove the hose from the power
steering Pump. Allow the remaining power steering
fluid to drain from the power steering pump and res-
ervoir through the removed return hose.
Fig. 3 Catalytic Converter to Exhaust Manifold
1 - CATALYTIC CONVERTER
2 - BOLT
3 - GASKET
4 - FLAG NUT
Fig. 4 Exhaust System - Typical (All Vehicles)
1 - CATALYTIC CONVERTER 4 - SUPPORT - RESONATOR
2 - BAND CLAMP 5 - RESONATOR
3 - SUPPORTS - MUFFLER 6 - MUFFLER
19 - 38 PUMPRS
PUMP (Continued)
(1) Install the pulley with Installer C-4063 (Fig.
15). Do not use the tool adapters.
(2) Ensure that the tool and the pulley remain
aligned with the pump shaft. Prevent the pulley from
being cocked on the shaft.
(3) Install the pulley until it is flush with the end
of the power steering pump shaft (Fig. 16).
(4) Install the power steering pump on the vehicle.INSTALLATION
INSTALLATION - PUMP (2.4L ENGINE)
(1) Install power steering pump back in vehicle
using the reverse order of its removal through the
exhaust tunnel of the vehicle.
(2) Install the power steering pump on its cast
mounting bracket (Fig. 7), then install the nut and
bolt attaching the front bracket to the cast bracket
(Fig. 8).Do not fully tighten at this time..
(3) Install the rear nut (Fig. 7).
(4) Install the power steering pump drive belt on
pulley and adjust (Refer to 7 - COOLING/ACCES-
SORY DRIVE/DRIVE BELTS - INSTALLATION).
(5) Tighten the two adjustment slot bolts and the
one pivot bolt to 54 N´m (40 ft. lbs.) torque.
(6) Install the accessory drive splash shield.
NOTE: Before installing power steering fluid pres-
sure hose on power steering pump, inspect the
O-ring on the pressure hose for damage and
replace if necessary.
(7) Install the power steering fluid pressure line
onto the output fitting of the power steering pump
(Fig. 6). Tighten the pressure line to pump fitting
tube nut to a torque of 31 N´m (275 in. lbs.).
(8) Install the power steering fluid low pressure
return hose on the power steering pump low pressure
fitting (Fig. 6).Be sure hose clamps are properly
reinstalled.
(9) Install the power steering fluid supply hose on
the power steering pump fluid fitting.Be sure hose
is clear of accessory drive belts all hose clamps
are properly reinstalled.
CAUTION: Heat sleeve must cover entire rubber
portion of return hose to ensure desired thermal
protection from exhaust.
(10) Properly position the protective heat sleeve
over the power steering return hose. Securely tie
strap the heat sleeve to the power steering hose to
keep in it's proper position.
(11)
Install the exhaust system (Fig. 4). Install all
exhaust system isolators/hangers on the exhaust sys-
tem brackets, then the four bolts and flag nuts (Fig. 3).
(12) Connect the oxygen sensor wiring harness to
the vehicle wiring harness.
(13) Lower vehicle.
(14) Connect the negative battery cable on the
negative battery post.
(15) Perform the POWER STEERING PUMP INI-
TIAL OPERATION procedure to properly fill and
bleed the power steering system. (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE)
(16) Inspect for leaks.
Fig. 15 Pulley Installation
1 - POWER STEERING PUMP DRIVE PULLEY
2 - SPECIAL TOOL
C-4063±A
Fig. 16 Pulley To Pump Shaft Location
1 - PULLEY
2 - PUMP BODY
3 - PUMP SHAFT
4 - HUB
19 - 42 PUMPRS
PUMP (Continued)
T850 MANUAL TRANSAXLE
TABLE OF CONTENTS
page page
T850 MANUAL TRANSAXLE
DESCRIPTION.........................21
OPERATION...........................24
DIAGNOSIS AND TESTING - COMMON
PROBLEM CAUSES....................30
REMOVAL.............................31
DISASSEMBLY.........................35
ASSEMBLY............................42
INSTALLATION.........................51
SPECIFICATIONS - T850 MANUAL
TRANSAXLE.........................56
SPECIAL TOOLS - T850 TRANSAXLE........58
AXLE SEALS
REMOVAL.............................61
INSTALLATION.........................61
BACK-UP LAMP SWITCH
REMOVAL.............................62
INSTALLATION.........................62
DIFFERENTIAL
DESCRIPTION.........................62
OPERATION...........................62
DISASSEMBLY.........................62
ASSEMBLY............................66
ADJUSTMENTS
ADJUSTMENT - DIFFERENTIAL TURNING
TORQUE............................69
ADJUSTMENT - DIFFERENTIAL SIDE GEAR
ENDPLAY...........................70
FLUID
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK.............................71
STANDARD PROCEDURE - FLUID DRAIN
AND FILL............................71
GEARSHIFT BOOT
REMOVAL.............................72
INSTALLATION.........................73GEARSHIFT CABLE - CROSSOVER
REMOVAL.............................73
INSTALLATION.........................76
ADJUSTMENTS
ADJUSTMENT........................79
GEARSHIFT CABLE - SELECTOR
REMOVAL.............................81
INSTALLATION.........................84
GEARSHIFT KNOB
REMOVAL.............................87
INSTALLATION.........................87
GEARSHIFT MECHANISM
REMOVAL.............................87
INSTALLATION.........................89
INPUT SHAFT
DESCRIPTION.........................93
DISASSEMBLY.........................93
ASSEMBLY............................96
INTERMEDIATE SHAFT
DESCRIPTION........................100
DISASSEMBLY........................100
ASSEMBLY...........................107
SHIFT COVER
DESCRIPTION........................113
SHIFT FORK AND SHAFT
DESCRIPTION........................113
SYNCHRONIZER
DESCRIPTION........................114
DISASSEMBLY........................114
CLEANING
CLEAN.............................114
INSPECTION
INSPECT...........................114
ASSEMBLY...........................114
VEHICLE SPEED SENSOR
REMOVAL............................115
INSTALLATION........................115
T850 MANUAL TRANSAXLE
DESCRIPTION
The NV T850 5-speed transaxle (Fig. 1) is a con-
stant-mesh manual transaxle that is synchronized in
all gear ranges, including reverse.The transaxle consists of three major sub-assem-
blies: the input shaft, intermediate shaft, and differ-
ential assembly. The transaxle shift system consists
of a mechanical shift cover, rails, forks, and cables.
The unique design of this shift system provides a
higher mechanical advantage, resulting in less fric-
tion and lower shift cable loads for smoother, more
positive operation.
RST850 MANUAL TRANSAXLE21-21