Testing Ignition System When Engine Will Not Start
- Disconnect the high tension wire at the distributor cap, and hold it approximately 1/2" from the engine block. Crank the engine. If spark occurs at the wire end, check the rotor and distributor cap. Ensure spark is reaching spark plugs.
- If no spark occurs, disconnect the connector at the distributor. Connect a jumper wire to pin "A" in the female connector leading to the electronic control unit. See Fig 1. With the ignition "ON", touch pin "C" with the other end of the jumper wire, and check for spark.
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- If no spark, go to next step. If spark, touch jumper wire between pins "A" and "C". Check for live condition at pin "B". If present, replace Hall sending unit in distributor. If no voltage, ensure wiring harness is good. If so, replace electronic control unit.
- If no spark occurred at pin "C" in step 2), check all wires and connectors carefully. If no fault is found, substitute a new electronic control unit. If there is still no spark, substitute a new ignition coil.