Caravan FWD V6-201 3.3L VIN R MFI (1997)
Shiny yellow glaze coating on the insulator.
POSSIBLE CAUSE
ACTION
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Metal By-products Of Combustion
- Avoid sudden acceleration with wide open throttle after long periods of low speed driving.
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Spark Plug Inspection
All engines use resistor spark plugs. They have resistance values ranging from 6,000 to 20,000 ohms when checked with at least a 1000 volt spark plug
tester.
Do not use an ohm meter to check the resistance of the spark plugs. This will give an inaccurate reading.
Remove the spark plugs and examine them for burned electrodes and fouled, cracked or broken porcelain insulators. Keep plugs arranged in the order in
which they were removed from the engine. An isolated plug displaying an abnormal condition indicates that a problem exists in the corresponding
cylinder. Replace spark plugs at the intervals recommended.
Spark plugs that have low mileage may be cleaned and reused if not otherwise defective, carbon or oil fouled.
The spark plugs are double platinum and have a recommended service life of 100,000 miles for normal driving conditions. The spark plugs have a
recommended service life of 75,000 miles for serve driving conditions. A thin platinum pad is welded to both electrode ends. Extreme care must be used
to prevent spark plug cross threading, mis-gaping and ceramic insulator damage during plug removal and installation.
CAUTION: Never attempt to file the electrodes or use a wire brush for cleaning platinum plugs. This would damage the platinum pads which
would shorten spark plug life.
Apply a very small amount of anti-seize compound to the threads when reinstalling the vehicle's original spark plugs that have been determined good. Do
not apply anti-seize compound to new spark plugs.
NOTE: Anti-seize compound is electrically conductive and can cause engine misfires if not applied correctly. It is extremely important that the anti-
seize compound doesn't make contact with the spark plug electrodes or ceramic insulator.
Never force a gap gauge between the platinum electrodes.
Always tighten spark plugs to the specified torque. Over tightening can cause distortion resulting in a change in the spark plug gap. Overtightening can
also damage the cylinder head.
Due to the engine packaging environment for the 3.3/3.8L engines, extreme care should be used when installing the spark plugs to avoid cross threading
problems.
Spark Plug Resistance Test
Resistance should be at least 6,000 to 20,000 ohms when checked with at least a 1000 volt tester.
Wet Oily Deposits
Symptoms: Electrodes coated with excessive wet fuel or oil.
Possible Causes:
-
In older engines, wet fouling can be caused by worn rings or excessive cylinder wear.
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In new or recently overhauled engines, fouling may occur before normal oil control is achieved. Break-in fouled spark plugs can be usually
be cleaned and installed.
White or Gray - Burned or Blistered Insulator
