Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Spark Plug Inspection
- Remove the ignition coils and the spark plugs .
- Inspect the electrodes and the ceramic insulator.
- Burned or worn electrodes may be caused by these conditions:
- Advanced ignition timing
- Loose spark plug
- Plug heat range too hot
- Insufficient cooling
- Fouled plugs may be caused by these conditions:
- Retarded ignition timing
- Oil in combustion chamber
- Incorrect spark plug gap
- Plug heat range too cold
- Excessive idling/low speed running
- Clogged air cleaner element
- Deteriorated ignition coils
- Burned or worn electrodes may be caused by these conditions:
- Replace the plug at the specified interval, or if the center electrode (A) is rounded, or if the spark plug gap (B) is out of specification, or if the spark plug electrode is dirty or contaminated. Use only the spark plugs listed.NOTE:
- Do not adjust the gap of iridium tip plugs.
- Do not use a plug cleaner.
J35Z6 engine
Spark Plugs
NGK: DILZKR7A11G
Electrode Gap
Standard (New): 1.0- 1.1 mm (0.039- 0.043 in)
J37A4 engine
Spark Plugs
NGK: ILZKR7B-11S
DENSO: SXU22HCR11S
Electrode Gap
Standard (New): 1.0- 1.1 mm (0.039- 0.043 in)
J35Z6 engine
J37A4 engine
- Install the spark plugs and the ignition coils.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.
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