FUEL FILTER
REMOVAL
(1) Release fuel pressure, refer to the Fuel release
procedure in this section.
(2) Disconnect the negative battery cable.
(3) Raise vehicle and support.
(4) Support the fuel tank with a transmission jack.
(5) Remove fuel line from the front of the tank.
(6) Remove ground strap
(7) Remove the inboard side of the fuel tank straps
and front T strap fastner.
(8) Lower the tank about 6 inches (Fig. 1).
(9) Remove fuel lines from the fuel pump module.
(10) Remove fuel filter from tank.
INSTALLATION
(1) Install fuel filter to tank. Tighten bolt to 4.5
N´m (40 in. lbs.)
(2) Install fuel lines to the fuel pump module (Fig.
1).
(3) Raise tank into position.
(4) Install the fuel tank straps.Tighten bolt for
main straps to 54 N´m (40 ft. lbs.) and the T strap
bolt to 28.2 N´m (250 in. lbs.)
(5) Install the ground strap
(6) Connect the fuel line at the front of the tank.
(7) Lower vehicle.
(8) Connect the negative battery cable.
(9) Pressurize the fuel system with the DRBIIIt
and check for leaks.
FUEL LEVEL SENDING UNIT /
SENSOR
DESCRIPTION
The fuel gauge level sending unit is attached to the
side of fuel pump module. The level sensor is a vari-
able resistor.
OPERATION
Its resistance changes with the amount of fuel in
the tank. The float arm attached to the sensor moves
as the fuel level changes.
The fuel level input is used as an input for OBD II.
If the fuel level is below 15% or above 85% of total
tank capacity several monitors are disabled. There
are diagnostics for the level circuit open and shorted.
REMOVAL
Remove fuel pump module. Refer to Fuel Pump
Module in this section.
(1) Depress retaining tab and remove the fuel
pump/level sensor connector from theBOTTOMof
the fuel pump module electrical connector (Fig. 2) .
NOTE: The pump module harness on TOP of flange
is not serviceable or removable.
Fig. 1 FUEL FILTER
Fig. 2 Fuel Pump/Level Sensor Electrical Connector
1 - ELECTRICAL CONNECTOR
2 - RETAINING TAB
14 - 4 FUEL DELIVERYRS
ProCarManuals.com
REMOVAL
(1) Remove fuel filler cap and perform Fuel Sys-
tem Pressure Release procedure (Fig. 15).
(2) Disconnect negative cable from battery.
(3) Insert fuel siphon hose into fuel filler neck and
push it into the tank.
(4) Drain fuel tank dry into holding tank or a
properly labeledGASOLINEsafety container.
(5) Raise vehicle on hoist and support.
(6) Use a transmission jack to support fuel tank.
Remove bolts from fuel tank straps.
(7) Lower tank slightly.
(8) Disconnect the fuel filler vent tube. Squeeze
tabs and pull apart (Fig. 16).
(9) Disconnect the fuel fill hose at the fuel tank
filler metal tubeNOT AT THE FUEL TANK(Fig.
16).
(10) Disconnect fuel line and vapor line at the
front of the fuel tank.
The fuel pump module electrical connector
has a retainer that locks it in place.
(11) Slide fuel pump module electrical connector
lock to unlock (Fig. 17).
(12) Push down on connector retainer (Fig. 18) and
pull connector off module.
(13) Lower tank from vehicle. Remove fuel filler
vent tube from frame (Fig. 19).
INSTALLATION
(1) Position fuel tank on transmission jack. Con-
nect rollover valve hose. Connect fuel filler tube vent
hose and tighten clamp.
(2) Raise tank into position and carefully work
filler metal tube into the rubber hose on fuel tank. A
light coating of clean engine oil on the tube end may
be used to aid assembly.
Fig. 15 Fuel Tank
1 - ROLLOVER VALVE
2 - FUEL FILLER INLET
3 - ROLLOVER VALVE
4 - GROUND STRAP
5 - FUEL FILTER
6 - FUEL PUMP MODULEFig. 16 FUEL FILLER AND VENT TUBE
1 - Filler Tube
2 - Vent Tube
Fig. 17 Fuel Line Retainers and Pump Connector
Lock
1 - PUSH
2 - CONNECTOR LOCK
3 - QUICK CONNECT RETAINERS
RSFUEL DELIVERY14-11
FUEL TANK (Continued)
ProCarManuals.com
(3) Feed filler vent line thru frame rail. Careful
not to cross lines.
(4) Tighten strap bolts to 54 N´m (40 ft. lbs.)
torque. Tighten T strap bolt to 28.2 N´m (250 in.
lbs.). Remove transmission jack.
(5) Tighten filler hose clamp to 3.3 N´m (30 in.
lbs.).
CAUTION: Ensure straps are not twisted or bent
before or after tightening strap nuts.
(6) Connect fuel pump/module electrical connector.
Place retainer in locked position.(7) Lubricate the fuel supply line with clean 30
weight engine oil, install the quick connect fuel fit-
ting. Refer to Tube/Fitting Assembly in the Fuel
Delivery section of this section.
(8) Attach filler vent line to filler tube. Pull on
connector to make sure of connection.
(9) Fill fuel tank, replace cap, and connect battery
negative cable.
(10) Use the DRBIIItscan tool to pressurize the
fuel system. Check for leaks.
FUEL TANK FILLER TUBE
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove the 3 screws at the filler door.
(3) Raise and support vehicle
(4) Remove the left rear tire.
(5) Remove the splash shield (Fig. 20).
(6) Remove the canister from filler tube (Fig. 21).
(7) Disconnect the vent at the top of the filler tube.
(8) Remove the ground strap.
(9) Remove filler tube at tank.
INSTALLATION
(1) Install filler tube to tank (Fig. 20).
(2) Install the ground strap.
(3) Connect the vent at the top of the filler tube.
Fig. 18 Pump Module Connector Retainer and Lock
1 - PUSH DOWN ON RETAINER
2 - CONNECTOR LOCK
Fig. 19 VENT HOSE
Fig. 20 FUEL FILLER TUBE AND VENT TUBE
14 - 12 FUEL DELIVERYRS
FUEL TANK (Continued)
ProCarManuals.com
Long Term
The second fuel correction program is the long
term adaptive memory. In order to maintain correct
emission throughout all operating ranges of the
engine, a cell structure based on engine rpm and load
(MAP) is used.
Ther number of cells varies upon the driving con-
ditions. Two cells are used only during idle, based
upon TPS and Park/Neutral switch inputs. There
may be two other cells used for deceleration, based
on TPS, engine rpm, and vehicle speed. The other
twelve cells represent a manifold pressure and an
rpm range. Six of the cells are high rpm and the
other six are low rpm. Each of these cells is a specific
MAP voltage range Typical Adaptive Memory Fuel
Cells .
As the engine enters one of these cells the PCM
looks at the amount of short term correction being
used. Because the goal is to keep short term at 0 (O2
Sensor switching at 0.5 volt), long term will updatein the same direction as short term correction was
moving to bring the short term back to 0. Once short
term is back at 0, this long term correction factor is
stored in memory.
The values stored in long term adaptive memory
are used for all operating conditions, including open
loop and cold starting. However, the updating of the
long term memory occurs after the engine has
exceeded approximately 170É-190É F, with fuel control
in closed loop and two minutes of engine run time.
This is done to prevent any transitional temperature
or start-up compensations from corrupting long term
fuel correction.
Long term adaptive memory can change the pulse-
width by as much as 25%, which means it can correct
for all of short term. It is possible to have a problem
that would drive long term to 25% and short term to
another 25% for a total change of 50% away from
base pulse-width calculation.
TYPICAL ADAPTIVE MEMORY FUEL CELLS
Open
ThrottleOpen
ThrottleOpen
ThrottleOpen
ThrottleOpen
ThrottleOpen
Throttle Idle Decel
Vacuum 20 17 13 9 5 0
Above 1,984
rpm1 3 5 7 9 11 13 Drive 15
Below 1,984
rpm02 4 6 8 1012
Neutral14
MAP volt =0 1.4 2.0 2.6 3.3 3.9
Fuel Correction Diagnostics
There are two fuel correction diagnostic routines:
²Fuel System Rich
²Fuel System Lean
A DTC is set and the MIL is illuminated if the
PCM detects either of these conditions. This is deter-
mined based on total fuel correction, short term
times long term.
PROGRAMMABLE COMMUNICATIONS
INTERFACE (PCI) BUS
DESCRIPTION
The Programmable Communication Interface Mul-
tiplex system (PCI Bus) consist of a single wire. The
Body Control Module (BCM) acts as a splice to con-
nect each module and the Data Link Connector
(DLC) together. Each module is wired in parallel to
the data bus through its PCI chip set and uses its
ground as the bus reference. The wiring is a mini-
mum 20 gage wire.
OPERATION
Various modules exchange information through a
communications port called the PCI Bus. The Power-
train Control Module (PCM) transmits the Malfunc-
tion Indicator Lamp (Check Engine) On/Off signal
and engine RPM on the PCI Bus. The PCM receives
the Air Conditioning select input, transaxle gear
position inputs over the PCI Bus. The PCM also
receives the air conditioning evaporator temperature
signal from the PCI Bus.
The following components access or send informa-
tion on the PCI Bus.
²Instrument Panel
²Body Control Module
²Air Bag System Diagnostic Module
²Full ATC Display Head (if equipped)
²ABS Module
²Transmission Control Module
²Powertrain Control Module
²Travel Module
²SKIM
14 - 20 FUEL INJECTIONRS
FUEL INJECTION (Continued)
ProCarManuals.com
INSTALLATION
(1) Position accelerator pedal assembly on dash
panel. Install retaining nuts. Tighten retaining nuts
to 12 N´m (105 in. lbs.) torque (Fig. 3).
(2) From inside the vehicle, hold up the pedal and
install the throttle cable and pedal retainer in the
upper end of the pedal lever (Fig. 2).
(3) From the engine compartment, hold the throt-
tle body lever in the wide open position and install
the throttle cable (Fig. 1).
CRANKSHAFT POSITION
SENSOR
DESCRIPTION
The 2.4L crankshaft sensor is located on the rear
of the engine near the accessory drive belt (Fig. 4).
The 3.3/3.8L crankshaft sensor is located on the rear
of the transmission housing, above the differential
housing (Fig. 5). The bottom of the sensor is posi-
tioned next to the drive plate.
Fig. 2 CABLE CLIP
Fig. 3 ACCELERATOR PEDAL
Fig. 4 CRANKSHAFT SENSOR 2.4L
Fig. 5 CRANKSHAFT SENSOR 3.3/3.8L
RSFUEL INJECTION14-23
ACCELERATOR PEDAL (Continued)
ProCarManuals.com
OPERATION
The crankshaft position sensor detects slots cut
into the transmission driveplate extension (Fig. 6).
There are 3 sets of slots. Each set contains 4 slots,
for a total of 12 slots (Fig. 7). Basic timing is set by
the position of the last slot in each group. Once the
Powertrain Control Module (PCM) senses the last
slot, it determines crankshaft position (which piston
will next be at TDC) from the camshaft position sen-
sor input. The 4 pulses generated by the crankshaft
position sensor represent the 69É, 49É, 29É, and 9É
BTDC marks. It may take the PCM one engine rev-
olution to determine crankshaft position.
The PCM uses crankshaft position reference to
determine injector sequence, ignition timing and the
presence of misfire. Once the PCM determines crank-
shaft position, it begins energizing the injectors in
sequence.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise vehicle and support.
(3) Disconnect the electrical connector (Fig. 8).
(4) Remove crankshaft sensor bolt.
(5) Remove the crankshaft sensor.
INSTALLATION - 2.4L
(1) Install the crankshaft sensor.
(2) Install crankshaft sensor bolt and tighten.
(3) Connect the electrical connector (Fig. 8).(4) Lower vehicle.
(5) Connect the negative battery cable.
ENGINE SPEED SENSOR
DESCRIPTION
The PCM receives a signal from the TCM and the
transaxle output speed sensor over the bus communi-
cation line to indicate vehicle speed on automatic
transmission cars. On Manual transmission cars (if
equipped) vehicle, a dedicated vehicle speed sensor is
connected to the PCM.
Fig. 6 Crankshaft Position Sensor
1 - CRANKSHAFT POSITION SENSOR
Fig. 7 Timing Slots
1 - TORQUE CONVERTER DRIVE PLATE
2 - SLOTS
Fig. 8 CRANKSHAFT SENSOR 2.4L
14 - 24 FUEL INJECTIONRS
CRANKSHAFT POSITION SENSOR (Continued)
ProCarManuals.com
OPERATION
The Transmission Control Module (TCM) supplies
the road speed and distance traveled inputs to the
PCM. From these inputs and the throttle position
sensor input, the PCM determines when a decelera-
tion condition occurs.
FUEL INJECTOR
DESCRIPTION
The injectors are positioned in the intake manifold
or cylinder head with the nozzle ends directly above
the intake valve port (Fig. 9).
OPERATION
The fuel injectors are 12 volt electrical solenoids
(Fig. 10). The injector contains a pintle that closes off
an orifice at the nozzle end. When electric current is
supplied to the injector, the armature and needle
move a short distance against a spring, allowing fuel
to flow out the orifice. Because the fuel is under high
pressure, a fine spray is developed in the shape of a
hollow cone or two streams. The spraying action
atomizes the fuel, adding it to the air entering the
combustion chamber. Fuel injectors are not inter-
changeable between engines.
The PCM provides battery voltage to each injector
through the ASD relay. Injector operation is con-
trolled by a ground path provided for each injector by
the PCM. Injector on-time (pulse-width) is variable,
and is determined by the PCM processing all the
data previously discussed to obtain the optimum
injector pulse width for each operating condition. Thepulse width is controlled by the duration of the
ground path provided.
REMOVAL
REMOVAL - 2.4L
The fuel rail must be removed first (Fig. 11). Refer
to Fuel Rail Removal in this section.
(1) Disconnect injector wiring connector from injec-
tor.
(2) Position fuel rail assembly so that the fuel
injectors are easily accessible (Fig. 12).
(3) Rotate injector and pull injector out of fuel rail.
The clip will stay on the injector.
(4) Check injector O-ring for damage. If O-ring is
damaged, it must be replaced. If injector is reused, a
protective cap must be installed on the injector tip to
Fig. 9 Fuel Injector Location - Typical
1 - FUEL RAIL
2 - INTAKE MANIFOLD
3 - FUEL INJECTORS
Fig. 10 FUEL INJECTOR - TYPICAL
1 - FUEL INJECTOR
2 - NOZZLE
3 - TOP (FUEL ENTRY)
Fig. 11 FUEL RAIL AND INJECTORS 2.4L
1 - Fuel Injectors
2 - Fuel Rail
RSFUEL INJECTION14-25
ENGINE SPEED SENSOR (Continued)
ProCarManuals.com
²Manifold pressure
²Injector pulse-width
²Spark-advance programs
²Shift-point strategies (F4AC1 transmissions
only, via the PCI bus)
²Idle speed
²Decel fuel shutoff
The PCM recognizes a decrease in manifold pres-
sure by monitoring a decrease in voltage from the
reading stored in the barometric pressure memory
cell. The MAP sensor is a linear sensor; as pressure
changes, voltage changes proportionately. The range
of voltage output from the sensor is usually between
4.6 volts at sea level to as low as 0.3 volts at 26 in. of
Hg. Barometric pressure is the pressure exerted by
the atmosphere upon an object. At sea level on a
standard day, no storm, barometric pressure is 29.92
in Hg. For every 100 feet of altitude barometric pres-
sure drops .10 in. Hg. If a storm goes through it can
either add, high pressure, or decrease, low pressure,
from what should be present for that altitude. You
should make a habit of knowing what the average
pressure and corresponding barometric pressure is
for your area.
REMOVAL
REMOVAL - 2.4L
(1) Disconnect the negative battery cable.
(2) Disconnect electrical connector and vacuum
hose from MAP sensor (Fig. 18).
(3) Remove two screws holding sensor to the
intake manifold.
REMOVAL - 3.3/3.8L
(1) Disconnect the negative battery cable.
(2) Remove vacuum hose and mounting screws
from manifold absolute pressure (MAP) sensor (Fig.
19).
(3) Disconnect electrical connector from sensor.
Remove sensor.
INSTALLATION
INSTALLATION - 2.4L
(1) Install sensor.
(2) Install two screws and tighten.
(3) Connect the electrical connector and vacuum
hose to the MAP sensor (Fig. 18).
(4) Connect the negative battery cable.
INSTALLATION - 3.3/3.8L
(1) Install sensor (Fig. 19).(2) Install screws and tighten toPLASTIC MAN-
IFOLD 1.7 N´m (15 in. lbs.) ALUMINUM MANI-
FOLD 3.3 N´m (30 in. lbs.).
(3) Connect the electrical connector to the sensor.
Install vacuum hose.
(4) Connect the negative battery cable.
O2 SENSOR
DESCRIPTION
The upstream oxygen sensor threads into the out-
let flange of the exhaust manifold (Fig. 20) or (Fig.
21).
Fig. 20 O2 SENSOR UPSTREAM 1/1 - 2.4L
Fig. 21 O2 SENSOR UPSTREAM 1/1 - 3.3/3.8L
14 - 30 FUEL INJECTIONRS
MAP SENSOR (Continued)
ProCarManuals.com