Cuts Out, Misses Symptom - Isuzu Trooper 1999 Workshop Manual

Step
1 DEFINITION:
Steady pulsation or jerking that follows engine speed;
usually more pronounced as engine load increases.
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. Check the PCM grounds for clearness, tightness
and proper routing.
diagrams in Electrical Diagnosis .
2. If a problem is found, repair as necessary.
Was a problem found?
5 Observe the long term fuel trim on the Tech 2.
Is the long term fuel trim significantly in the negative
range (rich condition)?
6 1. Check items that can cause the engine to run rich.
Refer to Diagnostic Aids in DTC P0172 Diagnostic
Support .
2. If a problem is found, repair as necessary.
Was a problem found?
7 Is the long term fuel trim significantly in the positive
range (lean condition)?
8 1. Check items that can cause the engine to run lean.
Refer to Diagnostic Aids in DTC P0171 Diagnostic
Support .
2. If a problem is found, repair as necessary.
Was a problem found?
9 1. Check for incorrect idle speed. Ensure that the
following conditions are present:
f
The engine is fully warm.
f
The accessories are "off."
2. Using a Tech 2, monitor the IAC position.
Is the IAC position within the specified values?
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Cuts Out, Misses Symptom

Action
Refer to the PCM wiring
Value(s) Yes
— Go to Step 2
— Go to Step 13
Go to Step 4
—
— Verify repair
— Go to Step 6
— Verify repair
— Go to Step 8
— Verify repair
Between 5
and 50
counts Go to Step 11
6E–453
No
Go to OBD
System
Check
Go to Step 3
Go to
Visual/Physic
al Check
Go to Step 5
Go to Step 7
Go to Step 9
Go to Step 9
Go to Step 9
Go to Step 10