Summit Wagon FWD L4-2350cc 2.4L SOHC (1995)
Spark Plug: Component Tests and General Diagnostics
1. Check the following items to see that electrodes are not burnt, and insulators are not broken, and how the porcelain insulator is burnt.
^
Broken insulators
^
Wearing electrodes
^
Deposited carbon
For cleaning, use a plug cleaner or wire brush. Clean porcelain insulator above shell as well.
^
Damaged or broken gasket.
^
Burnt condition of porcelain insulator at spark gap.
Dark deposit of carbon indicates too rich a fuel mixture or extremely low air intake. Also, misfiring due to excessive spark gap is suspected.
White burn indicates too lean a fuel mixture or excessively advanced ignition timing. Also insufficient plug tightening is suspected.
2. Clean with a plug cleaner. Use an air gun to remove dust deposited on plug threads.
Spark Plug Inspection: Step (3)
3. Check plug gap using a plug gap gauge and adjust if it is not as specified.
Standard value: 1.0 - 1.1 mm (0.039 - 0.043 in.)