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.
Secondary Wire Resistance Test
Test coil and spark plug cables with an ohmmeter. Do not puncture secondary wires when making the resistance check. Connect leads to each end of the cable. Resistance for Courier should not exceed 570 ohms per inch; for Mazda vehicles, resistance should not exceed 16, 000 ohms for each 39" (1 m); and Chrysler Corp. vehicles should not exceed 22, 000 ohms per cable.
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.