Isuzu 1999 RODEO Workshop Manual page 987

6E1–360 RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
LACK OF POWER, SLUGGISH OR
SPONGY SYMPTOM
DEFINITION:
Engine delivers less than expected power. Little or no
increase in speed when accelerator pedal is pushed down
part–way.
Step
1 Was the On–Board Diagnostic (OBD) System Check
performed?
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?
3 Was a visual/physical check performed?
4 1. Remove and check the air filter element for dirt or
restrictions. Refer to Air Intake System in
On–Vehicle Service.
2. Replace the air filter element if necessary.
Was a problem found?
5 Check for proper ignition voltage output with the spark
tester J 26792.
Was a problem found?
6 1. Remove the spark plugs and check 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?
7 Check the fuel pressure. Refer to Fuel System Test.
Was a problem found?
8 1. Install the Tech 2.
2. Run the engine at idle.
3. On the Tech 2, select F3: Miscellaneous Test, F6:
Variable Intake Manifold.
4. Repeat Switch ON or OFF of VIM solenoid valve by
using the Tech 2.
5. Check the solenoid working sound.
6. If a problem is found, repair as necessary.
Was a problem found?
9 Check for water or alcohol contaminated fuel.
Was a problem found?
10 Check the PCM grounds to verify that they are clean
and tight. Refer to the PCM wiring diagrams in
Electrical Diagnosis.
Was a problem found?
Action Value(s) Yes
— Go to Step 2
— Verify repair
— Go to Step 4
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
No
Go to OBD
System
Check
Go to Step 3
Go to Visual /
Physical
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 11