Spark Plug: Testing and Inspection

1993 Plymouth Laser FWD L4-1753cc 1.8L SOHCSECTION Testing and Inspection
Caution: If the spark plug cable is removed by pulling on the cable, it may be damaged.

1. Disconnect spark plug cable from the spark plug.
2. Using a plug wrench, remove all plugs from cylinder head.

Caution: Use care not to allow foreign matter to enter through plug holes.

3. Check the spark plugs for the following:
- Broken insulator
- Worn electrode
- Carbon deposits
- Damaged or broken gasket
- Burnt condition of porcelain insulator at spark gap.

Note: Dark deposits indicate too rich a fuel mixture, light (white) deposits indicate too lean a fuel mixture, advanced ignition timing or insufficient plug tightening

4. Check plug gap using a plug gap gauge and adjust if necessary.
Standard value: .028 - 0.031 in (.7 - .8 mm)
5. Tighten spark plug to specified torque. If overtorqueing occurs, damage to threaded portion of cylinder head might result.
Spark plug torque: 14-22 ft.lb (20 - 30 Nm)



RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.