2004 ISUZU TF SERIES coolant level

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-359
POOR FUEL ECONOMY SYMPTOM
DEFINITIONS: Fuel economy, as measured by an
actual road test, is noticeably lower than expected. Also,
economy is noticeably lower than it was on this vehicle
at one time, as previousl shown by an actual road test.
(Larger than standard tires will cause odomete
r
readings to be incorrect, and that may cause fuel
economy to appear poor when it is actually normal.)



Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go to On Board
Diagnostic (OBD)
System Check
2
1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
- Verify repair Go to Step 3
3
Was a visually/physical check performed?
- Go to Step 4 Go to Visual /
physical Check.
4
Check owner's driving habits.

Is the A/C On full time (defroster mode On)?

Are tires at the correct pressure?

Are excessively heavy loads being carried?

Is acceleration too much, too often?
- Go to Step 5 Go to Step 6
5
Review the items in Step 4 with the customer and
advise as necessary.
Is the action complete?
- System OK -
6
Visually/physically check: Vacuum hoses for splits,
kinks, and improper connections.
Was a problem found?
- Verify repair Go to Step 7
7
Check for low engine coolant level.
Was a problem found?
- Verify repair Go to Step 8
8
Check for incorrect or faulty engine thermostat. Refer
to Engine Cooling.
Was a problem found?
- Verify repair Go to Step 9
9
Remove and check the air filter element for dirt or for
restrictions.
Was a problem found?
- Verify repair Go to Step 10
10
Check the torque converter clutch (TCC) for proper
operation (if A/T model). If a problem is found, repair
as necessary.
Was a problem found?
- Verify repair Go to Step 11

6E-370 3.5L ENGINE DRIVEABILITY AND EMISSIONS
ENGINE COOLANT TEMPERATURE
(ECT) SENSOR

Location
Installed to the thermostat housing.

Removal Procedure
1. Disconnect the negative battery cable.
2. Drain enough engine coolant so that the coolan
t
level will be below the ECT sensor.
3. Disconnect connector from the ECT sensor.
4. Loosen and remove the ECT sensor from the
thermostat housing.
NOTE:
Cool down the engine before above procedures are
carried out.










Installation Procedure
1. Apply sealer to threads of screw at the ECT
sensor.
2. Tighten the ECT sensor with specified tightening
torque.
Tightening Torque





13N




m (1.3kgf




m)
3. Connect a ECT sensor connector to the ECT
sensor.
4. Fill the engine coolant.
5. Connect the negative battery cable.

NOTE:
Verify any DTCs (diagnosis Trouble Code) are not
stored after replacement.
Verify no engine coolant leaking from the senso
r
threads after replacement.


MASS AIR FLOW (MAF) SENSOR &
INTAKE AIR TEMPERATURE (IAT)
SENSOR
Location
Installed to the intake duct housing.

Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect a MAF & IAT sensor connector from
the MAF & IAT sensor.
3. Loosen two screws and remove the MAF & IAT
sensor from the intake duct.





Installation Procedure
1. Install the MAF & IAT sensor into intake air duct.
2. Tighten MAF & IAT sensor by two screws.
Tightening Torque : 1.5 N




m (0.15 kgf




m)
3. Connect a sensor connector to the MAF & IAT
sensor.
4. Connect the negative battery cable.

NOTE:
Verify any DTCs (diagnosis Trouble Code) are not
stored after replacement.

6-8 ENGINE DIAGNOSIS (C24SE)
Condition Possible cause Correction
Engine overheating Level of Engine Coolant too low Replenish
Thermo switch or fan motor
defective Replace
Thermostat defective Replace
Engine Coolant pump defective Correct or replace
Radiator clogged Clean or replace
Radiator filter cap defective Replace
Level of oil in engine crankcase
too low or wrong oil in engine Change or replenish
Resistance in exhaust system
increased Clean exhaust system or replace
defective parts
Throttle Position Sensor
adjustment incorrect Adjust Wide Open Throttle switch
setting
Throttle Position Sensor circuit
open or shorted Correct or replace
Cylinder head gasket damaged Replace
Cooling Fan clutch defective Replace
Fan belt slipping Adjust tension of V-belt or replace
V-belt
Engine overcooling Thermostat defective Replace (Use a thermostat set to
open at 92
C (197.6
F))
Engine lacks compression - Refer to Hard Start
Others Tire inflation pressure abnormal Adjust to recommend pressures
Brake drag Adjust
Clutch slipping Adjust or replace
Level of oil in engine crankcase
too high Correct level of engine oil

Engine Noisy
Abnormal engine noise often consists of various
noises originating in rotating parts, sliding parts and
other moving parts of the engine. It is, therefore,
advisable to locate the source of noise systematically.

Condition Possible cause Correction
Noise from crank journals or from
crank bearings
(Faulty crank journals and crank
bearings usually make dull noise
that becomes more evident when
accelerating) Oil clearance increased due to
worn crank journals or crank
bearings Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
Crankshaft out of round Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
Crank bearing seized Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing

ENGINE MECHANICAL (C24SE) 6A-63
OPERATIONS ON COOLING SYSTEM
Caution!
Before working with the cooling system, be sure to confirm that
the temperature of the engine is cooled down.
Failure to observe this may cause burn.








Cooling System, Check for Leaks
Installation
1. Install commercially available coolant checking
instrument onto compensation tank (Refer to section 6B;
Engine cooling).
2. Check coolant level.

Inspection
Use 5-8840-0277-0 tester & 5-8840-2603-0 adaptor.




Cooling System, Fill Up and Bleed
Important!
Radiator and heater core are made from alminium.
To avoid corrosion, use only anti-freeze with corrosion
protection.


Replace Coolant
1. Confirm the engine is cold enough.
2. Open the radiator cap, pour coolant to the filler neck level
and close the cap.
3. Pour coolant into the reservoir until MAX line is reached.
4. Start the engine, run 2 
3 minutes at idling speed and
switch off the engine.
5. Refill coolant if the coolant level is lowered.

6A-64 ENGINE MECHANICAL (C24SE)
Important!
Do not loosen or open the radiator cap when coolant is hot.
Doing so may cause hot water or steam to splash out, resulting
in burn. When opening the radiator cap, be sure to confirm the
coolant is cold. Cover a thick cloth over the cap and loosen it
slowly to reduce pressure, then open the cap.
6. Close the radiator cap firmly and run the engine at
approx. 2000 rpm. In addition, set the heater temperature
adjuster to the max position to circulate coolant in the
heater conduit system.
7. Confirm that the temperature gauge reads half or more
of full scale and that the thermostat is activated.
Then continue idling 5 minutes more and switch off the
engine, and allow it to cool.
8. After the engine cools down, check the coolant level and
refill it if necessary. When the level is lowered extremely,
check the coolant conduit system and reservoir hose for
leak.
9. Pour coolant into the reservoir to MAX level.







Refill Coolant
Important!
After closing the cooling system, let engine run warm until
thermostat opens (coolant approx. 92C/197.6F)

Inspection
Coolant level
Allow engine to cool. If necessary, refill coolant.

Check that cooling system self-bleeds during engine warming-
up phase.


Ignition Timing, Check
No Adjustment

6A-70 ENGINE MECHANICAL (C24SE)
Installation

(2.4L)
1. Install the ECM to the ECM bracket on engine.
2. Tighten the four screws to the bracket.
3. Connect the connector.









ECT
Removal
1. Remove wiring harness plug and coolant temperature
sensor.

Tighten (Torque)
Temperature sensor to intake pipe - 10 N

m (1.0 kgf

m)
Wiring harness plug to temperature sensor

Inspection
Coolant level







Idle Air Control (IAC) Valve
Removal
1. Remove wiring harness plug, hose clamps and idle
speed adjuster.

Installation
1. Install idle speed adjuster, hose clamps and wiring
harness plug.






Ignition Coil
Removal
1. Remove 2 bolts, plug and ignition coil.

Installation
1. Install ignition coil, plug and bolts.

ENGINE COOLING 6B-5
Diagnosis
Engine Cooling Trouble
Condition Possible cause Correction
Engine overheating Low Engine Coolant level Replenish
Thermo mater unit faulty Replace
Faulty thermostat Replace
Faulty Engine Coolant temperature
sensor Repair or replace
Clogged radiator Clean or replace
Faulty radiator cap Replace
Low engine oil level or use of
improper engine oil Replenish or change oil
Clogged exhaust system Clean exhaust system or replace
faulty parts
Faulty Throttle Position sensor Replace throttle valve assembly
Open or shorted Throttle Position
sensor circuit Repair or replace
Damaged cylinder head gasket Replace
Loosen V-belt tension Adjust belt tension or replace.
Collapsed hoses Replace
Faulty Fan clutch Replace
Engine overcooling Faulty thermostat Replace
Engine slow to warm-up Faulty thermostat Replace
Thermo unit faulty Replace

6B-6 ENGINE COOLING

















Draining and Refilling Cooling
System
Before draining the cooling system, inspect the system and
perform any necessary service to ensure that it is clean, does
not leak and is in proper working order. The engine coolant
(EC) level should be between the "MIN" and "MAX" lines of
reserve tank when the engine is cold. If low, check for leakage
and add EC up to the "MAX" line. There should not be any
excessive deposit of rust or scales around the radiator cap or
radiator filler hole, and the EC should also be free from oil.
Replace the EC if excessively dirty.
1. Completely drain the cooling system by opening the drain
plug at the bottom of the radiator.
2. Remove the radiator cap.
WARNING: TO AVOID THE DANGER OF BEING BURNED,
DO NOT REMOVE THE CAP WHILE THE ENGINE AND
RADIATOR ARE STILL HOT. SCALDING FLUID AND
STEAM CAN BE BLOWN OUT UNDER PRESSURE.
3. Disconnect all hoses from the EC reserve tank.
Scrub and clean the inside of the reserve tank with soap
and water. Flush it well with clean water, then drain it. Install
the reserve tank and hoses.
4. Refill the cooling system with the EC using a solution that is
at least 50 percent antifreeze.
5. Fill the radiator to the base of the filler neck.
Fill the EC reserve tank to "MAX" line when the engine is
cold.
6. Block the drive wheels and firmly apply the parking brake.
Shift an automatic transmission to "P" (Park) or a manual
transmission to neutral.
7. Remove the radiator cap. Start the engine and warm it up a
t
2,500 - 3,000 rpm for about 30 minutes.
8. When the air comes out from the radiator filler neck and the
EC level has gone down, replenish with the EC. Repeat this
procedure until the EC level does not go down. Then stop
the engine and install the radiator cap. Let the engine cool
down.
9. After the engine has cooled, replenish with EC up to the
"MAX" line of the reserve tank.
10. Start the engine. With the engine running at 3,000 rpm,
make sure there is no running water sound from the heate
r
core (behind the center console).
11. If the running water sound is heard, repeat steps 8 to 10.