2004 ISUZU TF SERIES power steering

ENGINE MECHANICAL (6VE1 3.5L) 6A-49
Engine Assembly
Removal

P1010068
1. Disconnect battery ground and positive cable.
2. Remove battery.
3. Make alignment mark on the engine hood and
hinges before removal in order to return the hood
to original position exactly.
4. Remove engine hood.
5. Drain radiator coolant.
6. Disconnect accelerator cable and automatic cruise
control cable from throttle valve on common
chamber.
7. Remove the ECM.

Disconnect the two connectors from the ECM.

. Remove fixing bolts on the common chamber.

Remove fixing bolts for ground cable.
8. Disconnect air duct with air cleaner cover.
9. Remove air cleaner assembly.
10. Disconnect canister vacuum hose.
11. Disconnect vacuum booster hose.
12. Disconnect three engine harness connectors.
13. Disconnect harness connector to transmission (lef
t
front side of engine compartment), disconnect shift
on the fly harness connector from front side o
f
front axle and remove transmission harness
bracket from engine left side.
14. Disconnect ground cable between engine and
frame.
15. Disconnect bonding cable connector on the back
of right dash panel.
16. Disconnect bonding cable terminal on the lef
t
bank.

17. Disconnect starter harness connector from starter.
18. Disconnect generator harness connector from
generator.
19. Disconnect coolant reserve tank hose from
radiator.
20. Remove radiator upper and lower hoses.
21. Remove upper fan shroud.
22. Remove cooling fan assembly four fixing nuts,
then the cooling fan assembly.
23. Move drive belt tensioner to loose side using
wrench then remove drive belt.
24. Remove power steering pump fixing bolts, then
power steering pump. Place the power steering
pump along with piping on the body side.
25. Remove air conditioning compressor fixing bolts
from bracket and place the compressor along with
piping on the body side.
26. Remove four O2 sensor harness connectors (two
each bank) from exhaust front pipe.
27. Remove three exhaust pipe fixing nuts from each
bank.
28. Remove two exhaust pipe fixing nuts from each
exhaust pipe, then move exhaust pipe to rear side
of vehicle.
29. Remove flywheel dust covers.
30. Disconnect two heater hoses from engine.
31. Disconnect fuel hose from right side o
f
transmission.
CAUTION: Plug fuel pipe on engine side and fuel
hose from fuel tank.
32. Remove transmission assembly. Refer to
Transmission section in this manual.
33. Support the engine by engine hoist.
34. Remove two left side engine mount fixing bolts
from engine mount on chassis side.
35. Remove two right side engine mount fixing bolts
from engine mount on chassis side.
36. Remove engine assembly.
Installation
CAUTION: When assembling the engine and
transmission, confirm that dowels have been
mounted in the specified positions at the engine
side. Also take care that dowel positions are
different between the manual transmission and the
automatic transmission. Otherweise, the
transmission may be damaged.

6A-50 ENGINE MECHANICAL (6VE1 3.5L)





012RS009
1. Install engine assembly. Tighten engine mount
fixing bolts to frame to the specified torque.
Torque: 41 N




m (4.2 kg




m/30 lb ft)
2. Reconnect fuel hose to fuel pipe on engine.
3. Install transmission assembly. Refer to
Transmission section in this manual.
4. Reconnect two heater hoses to engine.
5. Install flywheel dust covers.
6. Install exhaust pipe and temporally tighten two
(each bank) rear exhaust flange nuts then tighten
three stud nuts (each bank) between exhaus
t
manifold and exhaust pipe, finally tighten rear side
stud nuts to the specified torque.
Torque: 67 N




m (6.8 kg




m/49 lb ft)






LTW36FSH000101
7. Reconnect O2 sensor connector.
8. Install cooling fan assembly and tighten bolts/nuts
to the specified torque.
Torque: 25 N




m (2.5 kg




m/18 lb ft) for fan pulley
and fan bracket.
Torque : 10 N




m (1.0 kg




m/7 lb ft) for fan and
clutch assembly.
9. Install air conditioner compressor to engine and
tighten to the specified torque.
Torque : 43 N




m (4.4 kg




m/32 lb ft)
10. Install power steering pump, tighten fixing bolt to
the specified torque.
Torque :
M8 bolts : 25 N




m (2.5 kg




m/18 lb ft)
M10 bolts : 43 N




m (4.4 kg




m/32 lb ft)
11. Move drive belt tensioner to loose side using
wrench, then install drive belt to normal position.



850RW001
Legend
(1) Crankshaft Pulley
(2) Cooling Fan Pulley
(3) Tensioner
(4) Generator
(5) Air Conditioner Compressor
(6) Power Steering Oil Pump
(7) Drive Belt

12. Install upper fan shroud.
13. Reconnect radiator upper and lower hoses.
14. Reconnect coolant reserve tank hose to radiator.
15. Reconnect generator harness connector.
16. Reconnect starter harness connector.
17. Reconnect bonding cable terminal on left bank
18. Reconnect bonding cable terminal on the back o
f
right dash panel.

ENGINE COOLING (6VE1 3.5L) 6B-15
Drive Belt and Cooling Fan
Drive Belt and Associated Parts



015RW005
Legend (4) Water Pump and Cooling Fan Pulley
(1) Crankshaft Pulley (5) Idle Pulley
(2) Generator (6) Tension Pulley
(3) Power Steering Pump (7) Drive Belt


The drive belt adjustment is not required as automatic
drive belt tensioner is equipped.
Inspection
Check drive belt for wear or damage, and replace with a
new one as necessary.
Installation
Install cooling fan assembly and tighten bolts/nuts to the
specified torque.
Torque : 25 N




m (2.5 kg




m/18 lb ft) for fan pulley
and fan bracket.
Torque : 10 N




m (1.0 kg




m/7 lb ft) for fan and
clutch assembly.
NOTE: Fan belts for 6VE1 Gasoline Engine mounted on
98MY (UX) have been brought into one. As a result, the
rotating direction of a fan belt is opposite to the direction
of cooling fan for 92 to 97MY 6VD1 with no
interchangeability.
Therefore, incorrect installation of a fan may cause the
air for cooling to flow in the opposite direction, this
resulting in the poor performance of the air-conditione
r
and a rise temperature in engine cooling water.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-9




(1) Vehicle Speed Sensor (VSS)



(1) Power Steering Pressure Switch

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-47
Signal or Continuity Tester Position Pin
No. B/Box
No. Pin Function Wire
Color
Key SW Off Key SW On Engine IdleEngine
2000rpm ECM
Connection Range (+) (-)
B16 B16 Idle Air Control
(IAC) Valve
Coil A Low BLU/
RED Less than 1V Less than 1V / 10-14V Connect DC V B16 GND
B17 B17 Idle Air Control
(IAC) Valve
Coil B Low BLU/
BLKLess than 1V Less than 1V / 10-14V Connect DC V B17 GND
B18 B18 Check Engine
Lamp
(Immobilizer
Control Unit
Terminal B7) BRN/
YELLess than 1V Less than 1VLamp is turned on:
Less than 1V
Lamp is turned off: 10-14VConnect DC V B18 GND
B19 B19 Fuel Pump
Relay GRN/
WHT Less than 1V While relay is
activated:
10-14V
Relay is not
activated:
Less than 1V10-14V Connect DC V B19 GND
B20 B20 Mass Air Flow
(MAF) Sensor BLK/
YELLess than 1V Approx. 0.47VApprox. 1.5V
at 750 rpmApprox. 2V Connect DC V B20 GND
B21 B21 Bank 1 Oxygen
Sensor Signal PNK Less than 1V Approx. 0.4V 0.1 - 0.9V Connect DC V B21 B22
B22 B22 Bank 1 Oxygen
Sensor Ground BLU/
YELContinuity
with ground - - - Connect Ohm B22 GND
B23 B23 Bank 2 Oxygen
Sensor Signal RED Less than 1V Approx. 0.4V 0.1 - 0.9V Connect DC V B23 B24
B24 B24 Bank 2 Oxygen
Sensor Ground BLU/
BLKContinuity
with ground - - - Connect Ohm B24 GND
B25 B25 To Data Link
Connector
No.6 BLK/
GRN - - - - - - - -
B26 B26 Throttle
Position
Sensor (TPS)
Signal BLU Less than 1V Approx. 0.5V Approx. 0.6V Connect DC V B26 B39
B27 B27 TPS & Cam
Position
Sensor +5V
Supply GRN Less than 1V Approx. 5V Connect DC V B27 B39
B28 B28 Camshaft
Position (CMP)
Sensor Signal BLU - - Wave form - - - -
B29 B29 Inhibitor Switch
(AT Only) BLK Less than 1V P or N range: Less than 1V
Other than P or N range: 10-14V Connect DC V B29 GND
B30 B30 Power Steering
Pressure
Switch GRN/
YELLess than 1V Pressure switch is turned on: Less than 1V
Pressure Switch is turned off: 10-14V Connect DC V B30 GND
B31 B31 A/C Thermo
Relay GRN/
BLKLess than 1V A/C request is activated: 10-14V
A/C request is not activated: Less than 1VConnect DC V B31 GND

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-51

GENERAL DESCRIPTION FOR ECM AND
SENSORS
Engine Control Module (ECM)


1 2
(1) A Port
(2) B Port


The engine control module (ECM) is located on the
common chamber. The ECM controls the following.

Fuel metering system

Ignition timing

On-board diagnostics for powertrain functions.

The ECM constantly observes the information from
various sensors. The ECM controls the systems tha
t
affect vehicle performance. And it performs the
diagnostic function of the system.
The function can recognize operational problems, and
warn to the driver through the check engine lamp, and
store diagnostic trouble code (DTC). DTCs identify the
problem areas to aid the technician in marking repairs.

The input / output devices in the ECM include analog to
digital converts, signal buffers, counters and drivers.
The ECM controls most components with electronic
switches which complete a ground circuit when turned
on.

Inputs (Operating condition read):

Battery voltage

Electrical ignition

Exhaust oxygen content

Mass air flow

Intake air temperature

Engine coolant temperature

Crankshaft position

Camshaft position

Throttle position

Vehicle speed

Power steering pressure

Air conditioning request on or off

EGR valve position

Outputs (Systems controlled):

Ignition control

Fuel control

Idle air control

Fuel pump

EVAP canister purge

Air conditioning

Diagnostics functions

The vehicle with automatic transmission, the
interchange of data between the engine control module
(ECM) and the transmission control module (TCM) is
performed via a CAN-bus system.
The following signals are exchanged via the CAN-bus:

ECM to TCM:

ECM CAN signal status

Engine torque

Coolant temperature

Throttle position

Engine speed

A/C status

CAN valid counter

TCM to ECM:

Ignition timing retard request

Garage shift status

CAN valid counter

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-53
Idle Air Control (IAC) Valve








Step
CoilAB CD
Coil A High
(EC M B13)On On
Coil A Low
(EC M B16)On On
Coil B High
(EC M B14)On On
Coil B Low
(EC M B17)On On

(IAC Valve Close Direction)
(IAC Valve Open Direction)



The idle air control valve (IAC) valve is two directional
and gives 2-way control. It has a stepping moto
r
capable of 256 steps, and also has 2 coils. With power
supply to the coils controlled steps by the engine control
module (ECM), the IAC valve's pintle is moved to adjus
t
idle speed, raising it for fast idle when cold or there is
extra load from the air conditioning or power steering.
By moving the pintle in (to decrease air flow) or out (to
increase air flow), a controlled amount of the air can
move around the throttle plate. If the engine speed is
too low, the engine control module (ECM) will retract the
IAC pintle, resulting in more air moving past the throttle
plate to increase the engine speed.
If the engine speed is too high, the engine control
module (ECM) will extend the IAC pintle, allowing less
air to move past the throttle plate, decreasing the
engine speed.

The IAC pintle valve moves in small step called counts.
During idle, the proper position of the IAC pintle is
calculated by the engine control module (ECM) based
on battery voltage, coolant temperature, engine load,
and engine speed.
If the engine speed drops below a specified value, and
the throttle plate is closed, the engine control module
(ECM) senses a near-stall condition. The engine control
module (ECM) will then calculate a new IAC pintle valve
position to prevent stalls. If the IAC valve is disconnected and reconnected with
the engine running, the idle speed will be wrong. In this
case, the IAC must be reset. The IAC resets when the
key is cycled "On" then "Off". When servicing the IAC, i
t
should only be disconnected or connected with the
ignition "Off".
The position of the IAC pintle valve affects engine start-
up and the idle characteristic of the vehicle.
If the IAC pintle is fully open, too much air will be
allowed into the manifold. This results in high idle
speed, along with possible hard starting and lean
air/fuel ratio.

Camshaft Position (CMP) Sensor








12
(1) Camshaft Position (CMP) Sensor
(2) EGR Valve


With the use of sequential multi-point fuel injection, a
hall element type camshaft position (CMP) is adopted to
provide information to be used in making decisions on
injection timing to each cylinder. It is mounted on the
rear of the left-hand cylinder head and sends signals to
the ECM.
One pulse is generated per two rotations of crankshaft.

6E-80 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Tech 2
Parameter
Units Idle 2000rpm Definitions
23 A/C Request (Air
Conditioning) On/Off Off Off This displays the air conditioner request signal. This should display "On" when the air
conditioner switch is switched on.
24 A/C Clutch On/Off Off Off This displays whether the ECM has commanded the A/C compressor clutch "On" or
"Off".
25 EVAP Purge
Solenoid
(Evaporative
Emission) % 50
80 0 This displays the duty signal from the ECM to control the canister purge solenoid
valve.
26 Fuel Trim Cell 49
52 13
17 This displays dependent on engine speed and MAF sensor reading.
A plot of engine speed versus MAF amount is divided into the cells.
Fuel trim cell indicates which cell is currently active.
27 Fuel Pump On/Off On On This displays operating status for the fuel pump main relay.
This should display "On" when the key switch is turned on and while engine is
running.
28 Deceleration Fuel
Cutoff Active/ Inactive Inactive Inactive The ECM will command the deceleration fuel mode when it detects a closed throttle
position while the vehicle is traveling.
While in decreasing fuel mode, the ECM will decrease the amount of fuel delivered
by entering open loop and decreasing the injector pulse width.
29 Power Enrichment Yes/No No No The ECM will command power enrichment mode "Yes" when a large increase in
throttle position and load is detected.
While in power enrichment mode, the ECM will increase the amount of fuel delivered
by entering open loop and increasing the injector pulse width.
30 Vehicle Speed km/h or mph 0 0 This displays vehicle speed.
The vehicle speed is measured by ECM from the vehicle speed sensor.
31 Cam Signal Present/ Missing Present Present This displays input signal from the camshaft position sensor.
When the correct pulse is generated, signal is received.
32 PSP Switch
(Power Steering
Pressure) Normal Pressure /
High Pressure Normal PressureNormal PressureThis displays the power steering pressure signal.
This should display "High Pressure" when the steering is steered.
33 Security Code
Status Programmable/
Not
Programmable Programmable Programmable This should display "Programmable" when the correct security code & secret code
are programmed.
34 Security Code Okay/ Not Okay Okay Okay This should display "Okay" when the security code is correctly accepted.
35 Immobilizer
System Normal /
Abnormal Normal Normal This should display "Normal" when the immobilizer is correctly operated.
36 Malfunction
Indicator Lamp On/Off Off Off This displays operating status for the Check Engine Lamp.
This should display "On" when the Check Engine Lamp is turned on.
37 Time From Start   This displays the engine time elapsed since the engine was started.
If the engine is stopped, engine run time will be reset to 00:00:00