Isuzu 1999 RODEO Workshop Manual page 821

6E1–194 RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
DTC P0300 – Random/Multiple Cylinder Misfire Detected (Cont'd)
Step
9 1. Remove the spark plugs from the cylinders that
were indicated as misfiring.
2. Visually inspect the spark plug electrodes.
Does your inspection reveal any spark plugs exhibiting
excessive fouling?
10 1. Visually inspect the spark plug insulators for cracks,
carbon tracking, or other damage.
2. If a problem is found, replace the faulty spark
plug(s) as necessary.
Did your inspection reveal a problem?
11 Replace the ignition control module.
12 1. Inspect the PCM injector grounds, power grounds
and sensor grounds to ensure that they are clean,
tight and in their proper locations.
2. If a problem is found, correct the faulty ground
condition as necessary.
Did your inspection reveal a poor ground?
13 1. Perform the
procedure.
2. If a problem is found, repair as necessary (refer to
Engine Fuel or Fuel Metering System).
Was a fuel system problem found?
14 1. Check the fuel for excessive water, alcohol, or other
contaminants (refer to Diagnosis in Engine Fuel for
procedure).
Was the fuel contaminated?
15 1. Perform the "Injector Coil/Balance Test."
2. If a problem is found, replace the faulty injector(s) as
necessary.
Did any of the injectors require replacement?
16 Check for an engine mechanical problem. Refer to
Engine Mechanical Diagnosis to diagnose the following
conditions:
f
A faulty or incorrect camshaft
f
Leaking or sticky valves or piston rings
f
Excessive valve deposits
f
Loose or worn rocker arms
f
Weak valve springs
f
Incorrect valve timing
f
A leaking head gasket
f
A loose or broken motor mount
Action
"Fuel System Pressure
Value(s)
Go to Engine
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Test"
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Yes No
Mechanical
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Diagnosis 10
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Verify repair
11
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Verify repair 13
Go to Step
Verify repair
14
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15
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Verify repair 16
Verify repair —