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.
1985 Jeep Pickup J20FACTORY OEM SERVICE PROCEDURE
Secondary Circuit Check
CAUTION:
When checking secondary voltage, do not remove spark plug wires from spark plugs No. 3 on 4-cylinder, No. 1 or 5 on 6-cylinder and No. 3 or 4 on V8 Engines.
- Disconnect coil wire from distributor cap. Use insulated pliers to hold wire approximately 1/2" from engine block or intake manifold.
- Crank engine and check for spark at gap. If no spark occurs, turn off ignition switch, and check resistance of secondary coil windings. See IGNITION COIL RESISTANCE CHECK, SECONDARY RESISTANCE. Replace ignition coil if outside specifications.
- If spark occurred in step 2), connect coil wire to distributor cap. Remove wire from 1 spark plug. Using insulated pliers, hold wire 1/2" from engine head while cranking engine. Check for spark.
- If spark occurs, check for fuel problems or incorrect timing. If no sparks occur, check for defective rotor or distributor cap or for defective spark plug wires.
Factory Service Tools
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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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