Things You'll Need:
- Ohmmeter
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Step 1
Place the 3000GT's gear shift in "Park" and apply the emergency brake. Start the engine and allow it to idle.
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Step 2
Remove each spark plug from the engine, one at a time for two to three seconds. Use an insulated, pliers-style spark plug tool to grasp the spark plug boot.
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Step 3
Listen for a change in the engine performance when a plug is removed. The plug and/or wire may need replacing if their removal doesn't cause the performance to drop.
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Step 1
Disconnect a spark plug wire from the plug.
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Step 2
Connect a spark tester to the wire. Ground the tester to an appropriate metal location on the engine.
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Step 3
Crank the 3000GT's engine and check the tester. A strong blue spark should appear. Check the wire's resistance if a yellow-orange spark or no spark appears.
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Step 1
Unplug the electrical connector to the 3000GT's ignition coil. Be sure to disconnect it at the coil end.
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Step 2
Use an ohmmeter to measure the primary resistance between the coil's two terminals. The resistance should be 0.9 to 1.2 ohms for a 2.0L engine and 0.72 to 0.88 ohms on a 3.0L engine.
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Step 3
Measure the secondary resistance. Connect the ohmmeter to the secondary ignition coil terminal on the distributor cap and either terminal of the distributor connector. The resistance must be 20 to 29 kilo-ohms on a 2.0L engine, 10.29 to 13.92 kilo-ohms on a 3.0L.
