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.
12 13... Spark-plug faults
Evaluation of sparking period at idling speed.
- Normal ignition voltage peak Spark plug is OK.
- Low ignition voltage peak Small electrode gap.
- High ignition voltage peak Large electrode gap.
Evaluation of sparking period at idling speed.
Normal combustion period, spark plug is OK.
Long combustion period, small electrode gap.
Short sparking period, large electrode gap.
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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