2007 ISUZU KB P190 ignition

ENGINE DRIVEABILITY AND EMISSIONS 6E–233
ENGINE CRANKS BUT WILL NOT RUN
DEFINITIONS: Engine cranks, but will not run. (The engine never start.)
NOTE: The replacement ECM must be programmed. Refer to section of the Service Programming System (SPS) in
this manual. Following ECM programming, the immobilizer system (if equipped) must be linked to the ECM.
Refer to section 11 “Immobilizer System-ECM replacement” for the ECM/Immobilizer linking procedure.
NOTE: The vehicle with immobilizer system, this system may be activated. Check the immobilizer system diagosis.
Step Action Value(s) Yes No
1 Was the “ On-Board Diagnostic (OBD) System Check ”
performed? — Go to Step 2Go to
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 4Go to
Visual /
physical Check.
4 Check the “Ignition coil” fuse (15A) and “ECM” fuse (15A).
Was a fuse blown? — Verify repair Go to Step 5
5 1. Ignition ON 2. Use a DVM to verify that battery voltage at theignition coil fuse, and the ECM fuse.
Was battery voltage presented at the fuses? — Go to Step 6Verify & repair
6 1. Visually/physically inspect for the following conditions:
• Restriction of air intake system. Check for a restricted air filter element, or foreign objects
blocking the air intake system.
• Check for objects blocking the IAC passage or throttle bore, excessive deposits in the throttle
bore and on the throttle plate.
• Check for a condition that causes a large vacuum leak, such as an incorrectly installed or
faulty crankcase ventilation hose/brake booster
hose.
Was a problem found? — Verify repair Go to Step 7
7 1. Using a Tech 2, display the IAC value. 2. Check for a faulty, plugged, or sticking IACoperation.
Was the problem found? — Verify repair Go to Step 8
8 1. Using a Tech 2, display the MAP sensor value. 2. Check for a faulty, plugged, or incorrectly installedMAP sensor.
Was the problem found? — Verify repair Go to Step 9
9 If oscilloscope is available, check the wave form of the CKP signal.
Was the correct wave form found? — Go to Step 12Go to Step 10
10 Check the CKP sensor wire for open or short circuit. Was a problem found? — Verify repair Go to Step 11
11 Replace CKP sensor. Is there still problem? —Replace pulsar
ring. Verify repair

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–234 ENGINE DRIVEABILITY AND EMISSIONS
12 Visually/physically inspect the secondary ignitionwires. Check for the following conditions:
• Verify that all ignition wire resistance are less than the specified value.
• Verify that ignition wires are correctly routed to eliminate cross-fitting.
• Verify that ignition wires are not arcing to ground. Spraying the secondary ignition wires with a light
mist of water may help locate an intermittent
problem.
Was a problem found? #1 cyl. 4.4k
Ω
#2 cyl. 3.6k Ω
#3 cyl. 3.1k Ω
#4 cyl. 2.8k ΩVerify repair Go to Step 13
13 1. Disconnect the spark plug high tension cable from No.1 spark plug.
2. Install a spark tester at the end of the disconnected ignition coil.
3. Clip the spark tester to a good ground.
4. Observe the spark tester while the engine is cranking.
Was a crisp blue spark observed? (Only one or two
sparks followed by no result is considered the same
as “No Spark”.) — Go to Step 21Go to Step 14
14 1. Disconnect the ignition coil harness connector. 2. Check for an open or short circuit between theignition coil and the ECM.
Was a problem found? — Verify repair Go to Step 15
15 1. Ignition “On”. 2. Using a Digital Voltmeter (DVM) check the ignitionwire coil at the ignition coil harness connector.
Was the voltage equal to the specified value? Battery
voltage Go to Step 16Verify repair
16 1. Ignition “Off”. 2. With DVM, check for an open in the ground wire atthe ignition coil harness connector.
Was the ground wire OK? — Go to Step 17Verify repair
17 Replace the ignition coil, verify the repair. Attempt to start the engine.
Is there still a problem? — Go to Step 18Verify repair
18 Use an ohmmeter to check the ignition coil primary winding resistance.
Was the primary winding resistance approximately
equal to the specified value? 0.8-18kΩGo to Step 19 Go to Step 20
19 Use an ohmmeter to check the ignition coil secondary winding resistance.
Was the primary winding resistance hear around the
to the specified value? 2.5kΩ Go to Step 21 Go to Step 20
20 Replace the ignition coil. — Verify repair —
21 1. Remove the spark plugs from all cylinders. 2. Visually inspect the spark plug electrodes.
3. Replace any spark plugs with loose or missing electrodes or cracked insulators.
Did your inspection reveal any spark plugs exhibiting
excessive fouling? —Correct the
fouling
condition Go to Step 22
Step
Action Value(s) Yes No

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–236 ENGINE DRIVEABILITY AND EMISSIONS
HARD START SYMPTOM
DEFINITIONS: Engine cranks, but does not start for a long time. Does eventually start, of may start and then
immediately stall.
Step Action Value(s) Yes No
1 Was the “ On-Board Diagnostic (OBD) System Check ”
performed? — Go to Step 2Go to
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 4Go to
Visual /
physical Check.
4 1. Visually/physically inspect for the following conditions:
• Restriction of air intake system. Check for a restricted air filter element, or foreign objects
blocking the air intake system
• Check for objects blocking the IAC passage or throttle bore, excessive deposits in the throttle
bore and on the throttle plate
• Check for a condition that causes a large vacuum leak, such as an incorrectly installed or
faulty crankcase ventilation hose/brake booster
hose.
Was a problem found? — Verify repair Go to Step 5
5 1. Using a Tech 2, display the IAC value. 2. Check for a faulty, plugged, or sticking IACoperation.
Was the problem found? — Verify repair Go to Step 6
6 Check engine coolant temperature (ECT) sensor for shift in value.
1. After 8 hours with hood up and the engine not running, connect the Tech 2.
2. Ignition On, engine not running.
3. Using Tech 2, compare Engine Coolant Temperature to Intake Air Temperature.
Are ECT and IAT within the specified value of each
other? ± 5°C Go to Step 8Go to Step 7

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–237
7 1. Using a Tech 2, display the engine coolanttemperature and note the value.
2. Check the resistance of the engine coolant temperature sensor.
Is the actual resistance near the resistance value in
the chart for the temperature that was noted?
—Go to Step 8Replace the
ECT sensor. Verify repair
8 1. Using a Tech 2, display the MAP sensor value in comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed MAP sensor.
Was the problem found? — Verify repair Go to Step 9
9 Visually/physically inspect all spark plug high-tension cables. Check for the following conditions:
• Verify that the resistance of all spark plug high- tension cables are less than the specified value.
• Verify that the all spark plug high-tension cables are correctly fitted to eliminate cross-fitting.
• Verify that the all spark plug high-tension cables are not arcing to ground.
Spraying the spark plug high-tension cables with a
light mist of water may help locate an intermittent
problem.
Was a problem found? #1 cyl. 4.4k
Ω
#2 cyl. 3.6k Ω
#3 cyl. 3.1k Ω
#4 cyl. 2.8k ΩVerify repair Go to Step 10
10 Check for proper ignition voltage output with a spark tester.
Was the problem found? — Verify repair Go to Step 11
11 1. Remove the spark plugs and check for gas or oil fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must be determined before replacing the spark plugs.
Was a problem found? — Verify repair Go to Step 12
12 Check for a loose ignition control module ground. Was a problem found? — Verify repair Go to Step 13
13 1. Check the ignition coil secondary resistance. 2. Replace the coil if it is greater than the specifiedresistance.
Did the coil require replacement? 2.5kΩ Verify repair Go to Step 14
Step
Action Value(s) Yes No
Temperature (°C) Resistance (Ω) (Approximately)
-20 26740
0 9120
20 3500
40 1464
60 664
80 333
100 175
120 102

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–240 ENGINE DRIVEABILITY AND EMISSIONS
7 1. Using a Tech 2, display the engine coolanttemperature and note the value.
2. Check the resistance of the engine coolant temperature sensor.
Is the actual resistance near the resistance value in
the chart for the temperature that was noted?
—Go to Step 8Replace the
ECT sensor. Verify repair
8 1. Using a Tech 2, display the MAP sensor value in comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed MAP sensor.
Was the problem found? — Verify repair Go to Step 9
9 Using Tech 2, monitor throttle position with the engine idling.
Is the throttle position at the specified value and
steady?
0% Go to Step 10Refer to

Diagnostic
Trouble Code P0123 for further
diagnosis
10 Check for proper ignition voltage output with the spark tester.
Was a problem found? — Verify repair Go to Step 11
11 1. Remove the spark plugs and check for gas or oil fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must be determined before replacing the spark plugs.
Was a problem found? — Verify repair Go to Step 12
12 Check for a loose ignition control module ground. Was a problem found? — Verify repair Go to Step 13
13 Check items that can cause the engine to run rich. Refer to DTC P1167 “Fuel Supply System Rich During
Deceleration Fuel Cut Off”.
Was a problem found? — Verify repair Go to Step 14
14 Check items that can cause the engine to run lean. Refer to DTC P1171 “Fuel Supply System Lean
During Power Enrichment”.
Was a problem found? — Verify repair Go to Step 15
15 Check the injector connectors, if any of the injectors are connected any incorrect cylinder, correct as
necessary.
Was a problem found? — Verify repair Go to Step 16
16 1. Check for faulty engine mounts. 2. If a problem is found, repair as necessary.
Was a problem found? — Verify repair Go to Step 17
Step
Action Value(s) Yes No
Temperature (°C) Resistance (Ω) (Approximately)
-20 26740
0 9120
20 3500
40 1464
60 664
80 333
100 175
120 102

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–243
9 Check the fuel pressure. Refer to 6E-108 page“Fuel
System Diagnosis
”.
Was a problem found? — Verify repair Go to Step 10
10 Monitor “ B1S1 (Bank 1 Sensor 1) Status ” on the Tech
2.
Is the “ B1S1 (Bank 1 Sensor 1) Status ” in the rich
condition? — Verify repair Go to Step 11
11 Check items that can cause the engine to run rich. Refer to DTC P1167 “Fuel Supply System Rich During
Deceleration Fuel Cut Off”.
Was a problem found? — Verify repair Go to Step 12
12 Check items that can cause the engine to run lean. Refer to DTC P1171 “Fuel Supply System Lean
During Power Enrichment”.
Was a problem found? — Verify repair Go to Step 13
13 Check for proper ignition voltage output with the spark tester.
Was a problem found? — Verify repair Go to Step 14
14 Check for a loose ignition control module ground. Was a problem found? — Verify repair Go to Step 15
15 Visually/physically inspect all spark plug high-tension cables. Check for the following conditions:
• Verify that the resistance of all spark plug high- tension cables are less than the specified value.
• Verify that the all spark plug high-tension cables are correctly fitted to eliminate cross-fitting.
• Verify that the all spark plug high-tension cables are not arcing to ground.
Spraying the spark plug high-tension cables with a
light mist of water may help locate an intermittent
problem.
Was a problem found? #1 cyl. 4.4k
Ω
#2 cyl. 3.6k Ω
#3 cyl. 3.1k Ω
#4 cyl. 2.8k ΩVerify repair Go to Step 16
16 1. Check the ignition coil secondary resistance. 2. Replace the coil if it is greater than the specifiedresistance.
Did the coil require replacement? 2.5kΩ Verify repair Go to Step 17
17 1. Remove the spark plugs and check for gas or oil fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must be determined before replacing the spark plugs.
Was a problem found? — Verify repair Go to Step 18
18 1. Check the injector connectors. 2. If any of the connectors are connected at animproper cylinder, connect as necessary.
Was a problem found? — Verify repair Go to Step 19
19 Check the ECM grounds to verify that they are clean and tight. Refer to the ECM wiring diagrams.
Was a problem found? — Verify repair Go to Step 20
20 Visually/physically check the vacuum hose for splits, kinks and proper connections and routing.
Was a problem found? — Verify repair Go to Step 21
Step
Action Value(s) Yes No

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–246 ENGINE DRIVEABILITY AND EMISSIONS
10 Monitor “B1S1 (Bank 1 Sensor 1) Status ” on the Tech
2.
Is the “ B1S1 (Bank 1 Sensor 1) Status ” in the rich
condition? — Go to Step 11Go to Step 12
11 Check items that can cause the engine to run rich. Refer to DTC P1167 “Fuel Supply System Rich During
Deceleration Fuel Cut Off”.
Was a problem found? — Verify repair Go to Step 12
12 Check items that can cause the engine to run lean. Refer to DTC P1171 “Fuel Supply System Lean
During Power Enrichment”.
Was a problem found? — Verify repair Go to Step 13
13 Check for proper ignition voltage output with the spark tester.
Was a problem found? — Verify repair Go to Step 14
14 Check for a loose ignition control module ground. Was a problem found? — Verify repair Go to Step 15
15 Visually/physically inspect all spark plug high-tension cables. Check for the following conditions:
• Verify that the resistance of all spark plug high- tension cables are less than the specified value.
• Verify that the all spark plug high-tension cables are correctly fitted to eliminate cross-fitting.
• Verify that the all spark plug high-tension cables are not arcing to ground.
Spraying the spark plug high-tension cables with a
light mist of water may help locate an intermittent
problem.
Was a problem found? #1 cyl. 4.4k
Ω
#2 cyl. 3.6k Ω
#3 cyl. 3.1k Ω
#4 cyl. 2.8k ΩVerify repair Go to Step 16
16 1. Check the ignition coil secondary resistance. 2. Replace the coil if it is greater than the specifiedresistance.
Did the coil require replacement? 2.5kΩ Verify repair Go to Step 17
17 1. Remove the spark plugs and check for gas or oil fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must be determined before replacing the spark plugs.
Was a problem found? — Verify repair Go to Step 18
18 Check the ECM grounds to verify that they are clean and tight. Refer to the ECM wiring diagrams.
Was a problem found? — Verify repair Go to Step 19
19 Visually/physically check the vacuum hose for splits, kinks and proper connections and routing.
Was a problem found? — Verify repair Go to Step 20
Step
Action Value(s) Yes No

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–248 ENGINE DRIVEABILITY AND EMISSIONS
CUTS OUT, MISSES SYMPTOM
DEFINITIONS: Steady pulsation or jerking that follows
engine speed; usually more pronounced as engine load
increases.
Step Action Value(s) Yes No
1 Was the “ On-Board Diagnostic (OBD) System Check ”
performed? — Go to Step 2Go to
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 visual/physical check performed? —Go to Step 4Go to
Visual /
physical Check .
4 Check the ECM grounds to verify that they are clean and tight. Refer to the ECM wiring diagrams in
Electrical Diagnosis .
Was a problem found? — Verify repair Go to Step 5
5 Check for a loose or short circuit of ignition coil module voltage feed.
Was a problem found? — Verify repair Go to Step 6
6 Check for a loose or short circuit of ignition coil module ground.
Was a problem found? — Verify repair Go to Step 7
7 Visually/physically inspect all spark plug high-tension cables. Check for the following conditions:
• Verify that the resistance of all spark plug high- tension cables are less than the specified value.
• Verify that the all spark plug high-tension cables are correctly fitted to eliminate cross-fitting.
• Verify that the all spark plug high-tension cables are not arcing to ground.
Spraying the spark plug high-tension cables with a
light mist of water may help locate an intermittent
problem.
Was a problem found? #1 cyl. 4.4k
Ω
#2 cyl. 3.6k Ω
#3 cyl. 3.1k Ω
#4 cyl. 2.8k ΩVerify repair Go to Step 7
8 Check the CKP sensor wire, shield wire, or installation condition.
Was a problem found? — Verify repair Go to Step 9
9 Monitor “ B1S1 (Bank 1 Sensor 1) Status ” on the Tech
2.
Is the “ B1S1 (Bank 1 Sensor 1) Status ” in the rich
condition? — Go to Step 10Go to Step 11

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007