1998 ISUZU TROOPER open gas tank

6E±3 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0351
Ignition 1 Control Circuit 6E±206. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0352
Ignition 2 Control Circuit 6E±209. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0353
Ignition 3 Control Circuit 6E±212. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0354
Ignition 4 Control Circuit 6E±215. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0355
Ignition 5 Control Circuit 6E±218. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0356
Ignition 6 Control Circuit 6E±221. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0402
EGR Pintle Crank Error 6E±224. . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0404
EGR Open Stuck 6E±226. . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0405
EGR Low Voltage 6E±228. . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0406
EGR High Voltage 6E±231. . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0502
VSS Circuit Low Input 6E±234. . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0562
System Voltage Low 6E±237. . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0563
System Voltage High 6E±239. . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0601
PCM Memory 6E±240. . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P1154
HO2S Circuit Transition Time Ratio Bank 2
Sensor 1 6E±241. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P1171
Fuel System Lean During Acceleration 6E±245. . . .
Diagnostic Trouble Code (DTC) P1380
ABS Rough Road ABS System Fault 6E±248. . . . . .
Diagnostic Trouble Code (DTC) P1404
EGR Closed Stuck 6E±249. . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P1508
IAC System Low RPM 6E±251. . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P1509
IAC System High RPM 6E±254. . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P1618
Serial Peripheral Interface (SPI) PCM
Interprocessor Communication Error 6E±257. . . . . .
Diagnostic Trouble Code (DTC) P1625
PCM Unexpected Reset 6E±258. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P1640
Driver-1-Input High Voltage 6E±259. . . . . . . . . . . . . .
Symptom Diagnosis 6E±262. . . . . . . . . . . . . . . . . . . . .
Default Matrix Table 6E±288. . . . . . . . . . . . . . . . . . . . .
Camshaft Position (CMP) Sensor 6E±291. . . . . . . . . .
Crankshaft Position (CKP) Sensor 6E±292. . . . . . . . .
Engine Coolant Temperature (ECT) Sensor 6E±292.
Heated Oxygen Sensor (HO2S) 6E±293. . . . . . . . . . .
Intake Air Temperature (IAT) Sensor 6E±295. . . . . . .
Knock Sensor (KS) 6E±296. . . . . . . . . . . . . . . . . . . . . . Mass Air Flow (MAF) Sensor 6E±297. . . . . . . . . . . . .
Manifold Absolute Pressure (MAP) Sensor 6E±297.
Malfunction Indicator Lamp (MIL) 6E±298. . . . . . . . . .
Powertrain Control Module (PCM) 6E±298. . . . . . . . .
EEPROM 6E±300. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Steering Pressure (PSP) Switch 6E±300. . . .
Throttle Position (TP) Sensor 6E±301. . . . . . . . . . . . .
Vehicle Speed Sensor (VSS) 6E±302. . . . . . . . . . . . .
Air Cleaner/Air Filter 6E±303. . . . . . . . . . . . . . . . . . . . .
Idle Air Control (IAC) Valve 6E±304. . . . . . . . . . . . . . .
Common Chamber 6E±305. . . . . . . . . . . . . . . . . . . . . .
Accelerator Cable Assembly 6E±305. . . . . . . . . . . . . .
Accelerator Pedal Replacement 6E±308. . . . . . . . . . .
Fuel Filter Cap 6E±310. . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter 6E±310. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Gauge Unit 6E±313. . . . . . . . . . . . . . . . . . . . . . . .
Fuel Injectors 6E±314. . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Pressure Regulator 6E±315. . . . . . . . . . . . . . . . .
Fuel Metering System 6E±317. . . . . . . . . . . . . . . . . . . .
Fuel Pump Assembly 6E±318. . . . . . . . . . . . . . . . . . . .
Fuel Pump Relay 6E±319. . . . . . . . . . . . . . . . . . . . . . . .
Fuel Rail Assembly 6E±319. . . . . . . . . . . . . . . . . . . . . .
Fuel Tank 6E±321. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Throttle Body (TB) 6E±323. . . . . . . . . . . . . . . . . . . . . . .
Electronic Ignition System 6E±324. . . . . . . . . . . . . . . .
Catalytic Converter 6E±325. . . . . . . . . . . . . . . . . . . . . .
Air Conditioning Relay 6E±325. . . . . . . . . . . . . . . . . . .
EVAP Canister Hoses 6E±326. . . . . . . . . . . . . . . . . . . .
EVAP Canister 6E±326. . . . . . . . . . . . . . . . . . . . . . . . . .
EVAP Canister Purge Solenoid 6E±327. . . . . . . . . . . .
Fuel Tank Vent Valve 6E±328. . . . . . . . . . . . . . . . . . . .
Linear Exhaust Gas Recirculation
(EGR) Valve 6E±328. . . . . . . . . . . . . . . . . . . . . . . . . . .
Positive Crankcase Ventilation (PCV) Valve 6E±329.
Wiring and Connectors 6E±330. . . . . . . . . . . . . . . . . . .
PCM Connectors and Terminals 6E±330. . . . . . . . . . .
Wire Harness Repair: Twisted Shielded
Cable 6E±330. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Twisted Leads 6E±331. . . . . . . . . . . . . . . . . . . . . . . . . .
Weather-Pack Connector 6E±332. . . . . . . . . . . . . . . . .
Com-Pack III 6E±333. . . . . . . . . . . . . . . . . . . . . . . . . . .
Metri-Pack 6E±333. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Description 6E±335. . . . . . . . . . . . . . . . . . . . .
General Description (PCM and Sensors) 6E±335. . .
58X Reference PCM Input 6E±335. . . . . . . . . . . . . .
A/C Request Signal 6E±335. . . . . . . . . . . . . . . . . . . .
Crankshaft Position (CKP) Sensor 6E±335. . . . . . .
Camshaft Position (CMP) Sensor and
Signal 6E±335. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Coolant Temperature (ECT) Sensor 6E±335
Electrically Erasable Programmable Read
Only Memory (EEPROM) 6E±336. . . . . . . . . . . . . .
Fuel Control Heated Oxygen Sensors 6E±336. . . .
Intake Air Temperature (IAT) Sensor 6E±336. . . . .

6E±91 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Diagnosis

 
StepNo Ye s Value(s) Action
10Locate and repair the loss of vacuum to the fuel
pressure regulator.
Is the action complete?
ÐVerify repairÐ
11Replace the fuel pressure regulator.
Is the action complete?
ÐVerify repairÐ
121. Run the fuel pump with Tech 2.
2. After pressure has built up, turn off the pump and
clamp the supply hose shut with suitable locking
pliers.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant?
ÐGo to Step 13Go to Step 15
13Visually inspect the fuel supply line and repair any
leaks.
Was a problem found?
ÐVerify repairGo to Step 14
14Remove the fuel tank and inspect for leaky hose or
in-tank fuel line.
Was a problem found?
ÐVerify repairGo to Step 8
151. If the pliers are still clamped to the fuel supply hose,
remove the locking pliers.
2. With suitable locking pliers, clamp the fuel return
line to prevent fuel from returning to the fuel tank.
3. Run the fuel pump with Tech 2.
4. After pressure has built up, remove power to the
pump.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant?
ÐGo to Step 11Go to Step 16
16Locate and replace any leaking fuel injector(s).
Is the action complete?
ÐVerify repairÐ
17Is the fuel pressure indicated by the fuel pressure
gauge above the specified limit?376 kPa
(55 psi)
Go to Step 18Go to Step 21
181. Relieve the fuel pressure. Refer to the Fuel
Pressure Relief.
2. Disconnect the fuel return line from the fuel rail.
3. Attach a length of flexible hose to the fuel rail return
outlet passage.
4. Place the open end of the flexible hose into an
approved gasoline container.
5. Run the fuel pump with Tech 2.
6. Observe the fuel pressure indicated by the fuel
pressure gauge with the fuel pump running.
Is the fuel pressure within the specified limits?
290-376 kPa
(42-55 psi)
Go to Step 19Go to Step 20
19Locate and correct the restriction in the fuel return line.
Is the action complete?
ÐVerify repairÐ
20Visually and physically inspect the fuel rail outlet
passages for a restriction.
Was a restriction found?
ÐVerify repairGo to Step 11
21Is the fuel pressure indicated by the fuel pressure
gauge above the specified value?
0 kPa (0 psi)Go to Step 22Go to Step 23

6E±270
ENGINE DRIVEABILITY AND EMISSIONS
Detonation/Spark Knock Symptom

StepActionValue(s)Ye sNo
1DEFINITION:
A mild to severe ping, usually worse under acceleration.
The engine makes sharp metallic knocks that change
with throttle opening.
Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. 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?
ÐVerify repairGo to Step 3
3Was a visual/physical check performed?
ÐGo to Step 4
Go to
Visual/Physic
al Check
4If Tech 2 readings are normal (refer to Typical Scan
Values
) and there are no engine mechanical faults, fill
the fuel tank with a known quality gasoline that has a
minimum octane rating of 87 and re-evaluate the
vehicle performance.
Is detonation present?
ÐGo to Step 5Verify repair
51. Check the transmission range switch circuit. Use
Tech 2 and be sure Tech 2 indicates that the vehicle
is in drive with the gear selector in drive or overdrive.
2. If a problem is found, diagnose and repair the
transmission range switch as necessary (refer to
4L30-E Automatic Transmission Diagnosis).
Was a problem found?
ÐVerify repairGo to Step 6
61. Check TCC operation. Refer to 4L30-E
Transmission Diagnosis
.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 7
71. Check for obvious overheating problems:

Low engine coolant.

Restricted air flow to radiator, or restricted
water flow through radiator.

Correct coolant solution should be a 50/50 mix
of approved antifreeze/coolant and water.
Refer to
Engine Cooling.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 8
81. Check fuel pressure. Refer to Chart Fuel System
Pressure Test.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 9
91. Check items that can cause an engine to run lean
(long term fuel trim significantly in the positive
range). For a lean condition, refer to
Diagnostic
Aids
in DTC P0171 Diagnostic Support.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 10

6E±318
ENGINE DRIVEABILITY AND EMISSIONS
2. Remove the fuel pump relay from the underhood
relay box. Refer to
Fuel Pump Relay.
TS23976R
3. Start the engine and allow it to stall.
4. Crank the engine for 30 seconds.
5. Disconnect the negative battery cable.
Fuel Pump Assembly
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain all the fuel from the tank.
3. Install and tighten the drain plug.
Tighten

Tighten the drain plug to 20 N´m (14 lb ft.).
4. Remove the fuel tank. Refer to
Fuel Tank.
5. Remove the retaining screws from the fuel tank.
6. Remove the fuel pump assembly from the fuel tank.

Cover the fuel pump opening in order to prevent
dust, dirt, or debris from entering the fuel tank.
TS23795
Inspection Procedure
1. Inspect the fuel pump gasket for tears, cracks,
stretching, or rotting. If any of these conditions are
found, replace the fuel pump gasket.
2. Inspect the in-tank fuel filter for tears or evidence of
dirt, debris, or water in the fuel. If any of these
conditions are found, replace the in-tank fuel filter.
Installation Procedure
1. Install the fuel pump assembly.
2. Install the fuel pump assembly retaining screws.
3. Install the fuel tank assembly. Refer to
Fuel Tank.
4. Fill the tank with fuel.
5. Tighten the fuel filler cap.
6. Connect the negative battery cable.
TS23795

6E±342
ENGINE DRIVEABILITY AND EMISSIONS
PCM to calculate true sequential multiport fuel injection
(SFI). Loss of this signal will set a DTC P0341. If the CMP
signal is lost while the engine is running, the fuel injection
system will shift to a calculated sequential fuel injection
based on the last fuel injection pulse, and the engine will
continue to run. The engine can be restarted and will run
in the calculated sequential mode as long as the fault is
present, with a 1-in-6 chance of being correct.
Clear Flood Mode
Clear a flooded engine by pushing the accelerator pedal
down all the way. The PCM then de-energizes the fuel
injectors. The PCM holds the fuel injectors de-energized
as long as the throttle remains above 80% and the engine
speed is below 800 RPM. If the throttle position becomes
less than 80%, the PCM again begins to pulse the
injectors ªONº and ªOFF,º allowing fuel into the cylinders.
Deceleration Mode
The PCM reduces the amount of fuel injected when it
detects a decrease in the throttle position and the air flow.
When deceleration is very fast, the PCM may cut off fuel
completely for short periods.
Engine Speed/Vehicle Speed/Fuel Disable
Mode
The PCM monitors engine speed. It turns off the fuel
injectors when the engine speed increase above 6400
RPM. The fuel injectors are turned back on when engine
speed decreases below 6150 RPM.
Fuel Cutoff Mode
No fuel is delivered by the fuel injectors when the ignition
is ªOFF.º This prevents engine run-on. In addition, the
PCM suspends fuel delivery if no reference pulses are
detected (engine not running) to prevent engine flooding.
Fuel Injector
The sequential multiport fuel injection (SFI) fuel injector is
a solenoid-operated device controlled by the PCM. The
PCM energizes the solenoid, which opens a valve to allow
fuel delivery.
The fuel is injected under pressure in a conical spray
pattern at the opening of the intake valve. Excess fuel not
used by the injectors passes through the fuel pressure
regulator before being returned to the fuel tank.
A fuel injector which is stuck partly open will cause a loss
of fuel pressure after engine shut down, causing long
crank times.
0003
Fuel Metering System Components
The fuel metering system is made up of the following
parts:

The fuel injectors.

The throttle body.

The fuel rail.

The fuel pressure regulator.

The PCM.

The crankshaft position (CKP) sensor.

The camshaft position (CMP) sensor.

The idle air control (IAC) valve.

The fuel pump.

The fuel pump relay.
Basic System Operation
The fuel metering system starts with the fuel in the fuel
tank. An electric fuel pump, located in the fuel tank,
pumps fuel to the fuel rail through an in-line fuel filter. The
pump is designed to provide fuel at a pressure above the
pressure needed by the injectors. A fuel pressure
regulator in the fuel rail keeps fuel available to the fuel
injectors at a constant pressure. A return line delivers
unused fuel back to the fuel tank. Refer to
Section 6C for
further information on the fuel tank, line filter, and fuel
pipes.
Fuel Metering System Purpose
The basic function of the air/fuel metering system is to
control the air/fuel delivery to the engine. Fuel is delivered
to the engine by individual fuel injectors mounted in the
intake manifold near each intake valve.
The main control sensor is the heated oxygen sensor
(HO2S) located in the exhaust system. The HO2S tells
the PCM how much oxygen is in the exhaust gas. The
PCM changes the air/fuel ratio to the engine by controlling
the amount of time that fuel injector is ªON.º The best
mixture to minimize exhaust emissions is 14.7 parts of air
to 1 part of gasoline by weight, which allows the catalytic
converter to operate most efficiently. Because of the