Bad coil ?
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Cruiser
Joined: Nov 2007
Posts: 195
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From: Cheesehead threw and threw
Bad coil ?
Had posted a couple of weeks ago about engine stopping while going down the road. This weekend road early morning, later evening,cool, no problem, road early afternoon, stoped 5 times in 40 miles, sit a while , started. on way home, noon, warmer again, did same thing, ended up trailering, best I could tell, daylight, plug out of hole, cranking, no spark. Could it be coil,it has single fire ultima ignition,spyke coil, shorting out when hot, let it sit a while then it starts/runs for a while. Can it be tested ? Don't want to spend a $100.00 if thats not it. Thanks in advancee.
Cruiser
Joined: Sep 2007
Posts: 151
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From:
There is a way to test coils, but without knowing the specs it is not accurate.
The first way to test is to subsistute a "known to be good" coil.
My manual says to check primary and seconday resistance with an ohmmeter.
Check primary resistance by connecting your ohmmeter between the screw posts that the wires connect to. Stock coil is between 2.5 to 3.1 ohms.
Check secondary resistance by connecting your ohmmeter between the spark plug towers. Stock coil is between 10,000 and 12,500 ohms.
Hope this helps.
The first way to test is to subsistute a "known to be good" coil.
My manual says to check primary and seconday resistance with an ohmmeter.
Check primary resistance by connecting your ohmmeter between the screw posts that the wires connect to. Stock coil is between 2.5 to 3.1 ohms.
Check secondary resistance by connecting your ohmmeter between the spark plug towers. Stock coil is between 10,000 and 12,500 ohms.
Hope this helps.
Road Warrior
Joined: Dec 2008
Posts: 1,476
Likes: 23
From: Summit, Mississippi
If you have a single-fire, there are two coils involved. Either molded into one case or individual coils. It could be something with the battery feed to the coils/coil, which would be something common to both plugs not firing. It sounds like if you have a coil problem...it will be with the power two the coil. Of course, there could be some internal problem with a 2-into-1 coil too. If you place your ohmmeter across the two input terminals (not on the plug-tower side), like the post above said...you should have continuity in the form of very low resistance, but not a dead short or open. Make sure you have power to the coil. I don't recall if this is an EVO or not, but you also need to check the pick-up sensor. It's not likely you have a problem with the coil on the "plug" side. Like I said...you have an individual coil for each plug and you don't have either firing.
Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
Get a spray can of that coolant stuff that they sell at the electronics stores. When it starts acting up stop and spray it to cool it down. If the problem goes away you were right, if not keep looking.
Road Warrior
Joined: Dec 2008
Posts: 1,476
Likes: 23
From: Summit, Mississippi
Miacycles has a good idea and you can use brake parts or carburetor cleaner to cool-down components.
I need to clarify something from my earlier post. If you really have a single-fire, the input side of the coil will have three leads if it's a combined coil. One will be power and the other two will be signal leads from the ignition module or pick-up sensor. You could still have a problem on the primary (input side) though.
I need to clarify something from my earlier post. If you really have a single-fire, the input side of the coil will have three leads if it's a combined coil. One will be power and the other two will be signal leads from the ignition module or pick-up sensor. You could still have a problem on the primary (input side) though.
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Cruiser
Joined: Nov 2007
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From: Cheesehead threw and threw
Bought the "Cool" spray today and take it w/me for the next ride,to cool down the coil to verify it is the problem, hate to spend 100.00 if I don't have to. Have the "Ultima" single fire module down in the cone, right side, non adjustable. Spyke coil, don't recall how many leads, will probably take tank off tomarrow.
Could ignition modual, the one in the cone, be suspect also ?
Could ignition modual, the one in the cone, be suspect also ?
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Road Warrior
Joined: Dec 2008
Posts: 1,476
Likes: 23
From: Summit, Mississippi
Suspect everything. An overheated coil is a very good guess, but my experience is that when one goes open, it usually stays open. And another thing here, you are saying you have a single fire ignition, which requires 2 coil sections and 2 individual pick-ups. The sending unit down in the nosecone may look like one unit, but has two pick-ups in it. Squirt it good to cool it off also, but don't do both the coil and the pick-up at the same time. I lean to something loose in either the battery power feed to the coil or down there in the nosecone, but who knows. You can also shortcut your troubleshooting with a hair dryer too. You can heat-up the suspect components with the hair dryer to see if you can make something fail without doing all this out in the boondocks on the side of the road.
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Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
CT If you have the single fire ignition then you will have a power and two impulse leads. If the nose cone module is bad E-Mail me as we have an extra (don't ask) you can have.