Coil Check

Warning: The direct ignition system generates approximately 40,000 volts. personal injury could result from contact with this system.

Warning: Apply parking brake and/or block the wheels before performing any test with the engine running.

Caution: Spark plug cables may be damaged if this test is performed with more than 1/4 inch clearance between the cable and engine ground.

Note: Coil one fires cylinders 1 and 4, coil two fires cylinders 2 and 5, and coil three fires cylinders 3 and 6. Each coil tower is labeled with the number of the corresponding cylinder.

1. Remove the ignition cables and measure the resistance of the cables. Resistance must be between 3,000 to 12,000 ohms per foot of cable. Replace any cable not within tolerance.

2. Disconnect the electrical connector from the coil pack.

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 (Fig. 3). Resistance on the primary side of each coil should be 0.5 - 0.7 ohm. Replace the coil if resistance is not within tolerance.

Ignition Coil Terminal ID:

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 (Fig. 4). Secondary resistance should be 7,000 to 15,800 ohms. Replace the coil if resistance is not within tolerance.