Workshop Manual

6D2–5
IGNITION SYSTEM (6VE1 3.5L)
Spark Plug
Removal
1.Remove spark plugs.
Inspection and Repair
The spark plug affects entire engine performance and
therefore its inspection is very important.
B Check electrode and insulator for presence of cracks,
and replace if any.
B Check electrode for wear, and replace if necessary.
B Check gasket for damage, and replace if necessary.
B Measure insulation resistance with an ohmmeter, and
replace if faulty.
B Adjust spark plug gap to 1.0 mm – 1.1 mm (0.0394 in –
0.0433 in).
011RS011
NOTE:
– Do not adjust the spark plugs gap without new
spark plugs.
– Do not damage to tip of spark plugs.
– Do not cleaning the spark plugs. If require the
cleaning it due to heavy dirt, it is allowed only 20
seconds to be used spark plug cleaner.
B Check fuel and electrical systems if spark plug is
extremely dirty.
B Use spark plugs having low heat value (hot type plug)
if fuel and electrical systems are normal.
B Use spark plugs having high heat value (cold type
plug) if insulator and electrode are extremely burned.
Sooty Spark Plugs
Much deposit of carbon or oil on the electrode and
insulator of spark plug reduces the engine performance.
Possible causes:
B Too rich mixture
B Presence of oil in combustion chamber
B Incorrectly adjusted spark plug gap
Burning Electrodes
This fault is characterized by scorched or heavily oxidized
electrode or blistered insulator nose.
Possible causes:
B Too lean mixture
B Improper heat value
Measuring Insulation Resistance
B Measure insulation resistance using a 500 volt
megaohm meter.
B Replace spark plugs if measured value is out of
standard.
Insulation resistance: 50 MW or more
011RS010
Installation
1.Spark plugs
B Tighten spark plugs to the specified torque.
Torque: 18 N·m (13 lb ft)