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  • avatar karjunkie 04/16/09 2:03 pm PST

    Did you test the ignition coil? This testing procedure is valid for just about any automotive coil. Using an ohmmeter, check the resistance between the side terminals of the coil. Do this with all of the wires to the coil disconnected. You should see 0.75 to 0.81 ohm of resistance. Then check the resistance between either side terminal and the center high tension terminal. The reading should be 10,000 to 11,000 ohms. Any significant deviation from these numbers would indicate that the coil is defective.

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  • karjunkie 04/16/09 2:03 pm PST

    Did you test the ignition coil? This testing procedure is valid for just about any automotive coil. Using an ohmmeter, check the resistance between the side terminals of the coil. Do this with all of the wires to the coil disconnected. You should see 0.75 to 0.81 ohm of resistance. Then check the resistance between either side terminal and the center high tension terminal. The reading should be 10,000 to 11,000 ohms. Any significant deviation from these numbers would indicate that the coil is defective.

  • cruzinsaab 04/17/09 1:30 am PST

    This afternoon the problem was solved. It was NOT any of the following:

    Fuel pump
    fuel regulator
    Injectors
    cap and rotor, wires
    computer and wires

    Tech noticed that the misfire was only on #5, but as it rev'ed to road speed, misfire stopped. Our compression check was OK. Tech supected a sticky(slow to close) valve so we used a valve guide additive in the oil. Ran engine at a high idle for about an hour and the misfire cleared up. Tech said that 5.7 engines have a history of doing this once they get over 75K miles. I wonder how many heads had been pulled for valve grinds when a $5.00 valve guide cleaner would have done it.....JD

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