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Ignition Coil Test

Coil one fires cylinders 1 and 4, coil two fires cylinders 2 and 3. Each coil tower is labeled with the number of the corresponding cylinder.

1. Remove ignition cables and measure the resistance of the cables. Resistance must be within the range shown in the Cable Resistance Chart in Specifications. Replace any cable not within tolerance.
2. Disconnect the electrical connector from the coil pack.

Terminal Identification:




3. Measure the primary resistance of each coil. At the coil, connect an ohmmeter between the B+ pin and the pin corresponding to the cylinders in question. Resistance on the primary side of each coil should be 0.45-0.65 ohm at (70° to 80°F). Replace the coil if resistance is not within tolerance.

Checking Ignition Coil Secondary Resistance:




4. Remove ignition cables from the secondary towers of the coil. Measure the secondary resistance of the coil between the towers of each individual coil. Secondary resistance should be 7,000 to 15,800 ohms. Replace the coil if resistance is not within tolerance.