Lack Of Power, Sluggish Or Spongy Symptom - Isuzu C22NE Workshop Manual

6E1-86 DRIVEABILITY AND EMISSIONS
Step
DEFINITION: Engine delivers less than expected power. Little or no increase in speed when accelerator pedal is
pushed down part-way.
Was the On-Board Diagnostic (OBD) System Check
1 performed?
1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
2
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
Was a visual/physical check performed?
3
1. Remove and check the air filter element for dirt or
restrictions. Refer to Air Intake System in On-Vehicle
4 Service.
2. Replace the air filter element if necessary.
Was a repair required?
Check for proper ignition voltage output with the spark
5 tester (Use commercially available tool).
Was a problem found?
1. Remove the spark plugs and check for gas or oil
fouling, cracks, wear, improper gap, burned electrodes,
heavy deposits or improper heat range.
6
2. If spark plugs are fouled, the cause of fouling must be
determined before replacing the spark plugs.
Was a problem found?
Check the fuel pressure. Refer to Fuel System Pressure
7 Test.
Was a problem found?
Check for water or alcohol contaminated fuel.
8
Was a problem found?
Check the ECM grounds to verify that they are clean and
tight. Refer to the ECM wiring diagrams in Electrical
9
Diagnosis.
Was a problem found?
Check the exhaust system for a possible restriction:
• Damaged or collapsed pipes
10
• Internal muffler failure
Was a problem found?

Lack of Power, Sluggish or Spongy Symptom

Action Value(s) Yes
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Go to Step 2
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Verify Repair
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Go to Step 4
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Verify repair
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Verify repair
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Verify repair
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Verify repair
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Verify repair
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Verify repair
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Verify repair
No
Go to OBD
System
Check
Go to Step 3
Go to
Visual/Physic
al Check
Go to Step 5
Go to Step 6
Go to Step 7
Go to Step 8
Go to Step 9
Go to Step 10
Go to Step 10