IGNITION COIL AND BALLAST RESISTOR

2.0L and 2.6L Engines

1. Measure the resistance of the external resistor on the coil by connecting the probes of an ohmmeter across the two resistor connectors. Resistance should be as follows or the unit should be replaced.
   • 2.0L engine (1983–86): 1.35 ohms
   • 2.0L engine (1987–89): 1.2–1.4 ohms
   • 2.6L engine (1983–86): 1.04–1.27 ohms
   • 2.6L engine (1987–88): 1.25 ohms
   • 2.6L engine (1989–90): 1.12–1.38 ohms
2. Measure the resistance across the coil primary circuit by connecting an ohmmeter between the (+) and (−) coil connectors. Resistance must be approximately as follows or the coil should be replaced.
   • 2.0L engine (1983–86): 1.2 ohms
   • 2.0L engine (1987–89): 1.08–1.32 ohms
   • 2.6L engine (1983–86): 1.04–1.27 ohms
   • 2.6L engine (1987–88): 1.25 ohms
   • 2.6L engine (1989–90): 1.12–1.38 ohms
3. Set your ohmmeter to the x1000 scale and measure the resistance between the connector inside the coil tower and the coil (+) terminal. This is secondary resistance and must be as follows, or the unit should be replaced.
   • 2.0L engine (1983–86): 1.2 kilohms
   • 2.0L engine (1987–89): 1.08–1.32 kilohms
   • 2.6L engine (1983–86): 7.1–9.6 kilohms
   • 2.6L engine (1987–88): 11.0 kilohms
   • 2.6L engine (1989–90): 9.4–12.7 kilohms
4. Inspect the unit for oil leaks and cracks in the coil tower, and replace it if any defects are noted.

   Fig. 1: Checking the resistance of the external resistor

   Fig. 2: Checking primary coil resistance

   Fig. 3: Checking secondary coil resistance

2.4L and 3.0L (12 Valve) Engines

1. Measure the resistance across the coil primary circuit by connecting an ohmmeter between the (+) and (−) coil connectors. Resistance must be approximately 0.72–0.88 ohms or the coil should be replaced.
2. Set your ohmmeter to the x1000 scale and measure the resistance between the connector inside the coil tower and the coil (+) terminal. This is secondary resistance and must be 10.3–13.9 kilohms, or the unit should be replaced.
3. Inspect the unit for cracks in the coil tower, and replace it if any defects are noted.

   Fig. 4: Coil assembly for the 2.4L and 3.0L (12 valve) engines

3.0L (24 Valve) Engines

1. To test the primary coil resistance, measure the resistance between the terminal (1) of the connector (power source) and the terminals of each coil.

   Measurement points:

   • A coil: Terminals 1 and 11
   • B coil: Terminals 1 and 13
   • C coil: Terminals 1 and 12

   Standard value: 0.67–0.81 ohms

2. To test the secondary coil resistance, switch the ohmmeter to the x1000 scale and measure the resistance between each terminal for a high pressure.

   Measurement points:

   • A coil
   • B coil
   • C coil

   Standard value: 11.3–15.3 kilohms

3. Inspect the unit for cracks and replace it if any defects are noted.

   Fig. 5: The primary coil configuration and resistance check — 3.0L (24 valve) engine

   Fig. 6: Checking secondary coil resistance — 3.0L (24 valve) engine

3.5L Engines

1. To test the primary coil resistance, measure the resistance between the terminals for each cylinder (No. 1 & No. 4, No. 2 & No. 5, No. 3 & No. 6) of the ignition coil.

   Standard value: 0.69–0.85 ohms

2. To test the secondary coil resistance, switch the ohmmeter to the x1000 scale and measure the resistance between the high voltage terminals for each cylinder (No. 1 & No. 4, No. 2 & No. 5, No. 3 & No. 6) of the ignition coil as shown in the illustration.

   Standard value: 15.3–20.7 kilohms

3. Inspect the unit for cracks and replace it if any defects are noted.

   Fig. 7: Checking the primary ignition coil resistance — 3.5L engine

   Fig. 8: Checking secondary ignition coil resistance — 3.5L engine