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Ignition coil going out

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  • Ignition coil going out

    I have a 1997 Johnson 175 V6 and I have bought 2 ignition coils because it keeps on going bad. This is the upper coil. Am I having trouble with the power pack or is it just that I'm out of luck and the coils I'm buying are defective. I did buy from amazon not original from Johnson I did buy it original and should arrive in a few days. Please any suggestions before installing new coil???

  • #2
    How do you know the coil is "going bad"?

    Do this: Set your multimeter to 1K ohms resistance, and check the circuit between the clip in the plug boot and a clear spot on the block. You should see about 5k ohms or so -- check each of the coils the same way and see if readings are similar for all.

    Check spark with an open air spark tester (not the inline variety). Set the tester for 1/2" and test -- other plugs removed.

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    • #3
      Oldboat 1 Thanks for the reply, so if im getting more resistance on the upper coil does that me mean I have a bad power pack?


      • #4
        Coils ( factory ) are very reliable.-----What other trouble shooting has been done ?----What torque value are you using to install the coils ?


        • #5
          Chances are it is not a bad coil. I would do the open air spark test (device is $10 or so at an auto parts store). If you get no spark on the top coil, check the plug wire for continuity boot to boot.

          [Edit. If it turns out after testing that you have spark, consider the possibility that the plug/cylinder is water-washed. Perhaps a bad head gasket.]
          Last edited by oldboat1; January 13th, 2020, 05:40 PM.


          • #6
            A 1997 should have the "package coil" (2 coils in same casting). If it has a single coil its not a 1997. If its the package type make sure RFI shield is in place and grounding washers installed.
            When in doubt,Trim it out!!!
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            • #7
              Oldboat 1 my explanation is that I change the middle one to the top and the bad one to the middle and it gives me spark on the top one and no spark in the middle coil. I will update as soon as I get the new coil. I just didnt want to throw the new coil in there before doing any TS.
              Last edited by Toyoluiis; January 14th, 2020, 09:06 AM.


              • #8
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                It has six coils in 3 housings / assemblies.