Isuzu 1999 RODEO Workshop Manual page 1000

CUTS OUT, MISSES SYMPTOM
DEFINITION:
Steady pulsation or jerking that follows engine speed;
usually more pronounced as engine load increases.
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 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?
5 Monitor "Long Term Fuel Trim" on the Tech 2.
Is the "Long Term Fuel Trim" in the negative range (rich
condition)?
6 Check items that can cause the engine to run rich.
Refer to "Diagnostic Aids" in DTC P0172.
Was a problem found?
7 Is the long term fuel trim significantly in the positive
range (lean condition)?
8 Check items that can cause the engine to run lean.
Refer to Diagnostic Aids in DTC P0171.
Was a problem found?
9 1. Check for incorrect idle speed. Ensure that the
following conditions are present:
f
Engine fully warm.
f
Accessories are OFF.
2. Using a Tech 2, monitor the IAC position.
Is the IAC position within the specified values?
10 1. Visually/physically
conditions:
f
Restricted air intake system. Check for a
restricted air filter element, or foreign objects
blocking the air intake system.
f
Check for objects blocking the IAC passage or
throttle bore, excessive deposits in the IAC
passage and on the IAC pintle, and excessive
deposits in the throttle bore and on the throttle
plate.
f
Check for a condition that causes a large
vacuum leak, such as an incorrectly installed
or faulty crankcase ventilation valve or brake
booster hose disconnected.
Was a problem found?
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
Action
inspect for the following
Value(s) Yes
— Go to Step 2
— Verify repair
— Go to Step 4
— Verify repair
— Go to Step 6
— Verify repair
— Go to Step 8
— Verify repair
Between 5
and 50
Go to Step 11
counts
— Verify repair
6E1–373
No
Go to OBD
System
Check
Go to Step 3
Go to Visual /
Physical
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
Go to Step 11