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.
Ignition System - Service Information: Description
The High Energy Ignition (HEI) system uses one coil and two spark plugs per cylinder. Individual coils for each cylinder ensure consistent performance at high RPM and allow individual cylinder spark control. Dual spark plugs provide more complete combustion, particularly near the cylinder walls, thus decreasing emissions. Also, HEI enhances combustion efficiency when firing mixtures diluted by EGR (Exhaust Gas Recirculation), which in turn improves overall efficiency and lowers emissions.
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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