1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Small ignition (I think) problem

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Old Dec 17, 2007 | 01:43 AM
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Small ignition (I think) problem

12a, '85 GSL

If I let the car sit a couple days without driving it, and it rains//snows, the past couple times when I start it up, its running on a single rotor for the first while, eventually firing on the second. The couple times its done this to me I havn't been able to check it out too thoroughly, because it always seems to happen when I'm in a rush, and its dark.

Anyone have any ideas on what this might be? I'm guessing moisture is getting into the ignition somewhere, need a new dizzy cap possibly?
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Old Dec 17, 2007 | 03:05 AM
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Are you sure it's running on 1 rotor? It could be running on leading or trailing ignition only. Let it sit, take the wire off the leading coil and crank the car. Look for spark. If you get spark hook it back up an try the trailing side. If both check out then check your plug wires
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Old Dec 17, 2007 | 08:39 AM
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you could have moisture in your cap causing arcing inside the cap. you'll want to inspect the trailing igintion using the method listed above by removing a plug wire from a trailing pulg. i then use a spark plug off the shelf and insert it into the wire and ground it to the strut tower and crank. this allows me to see the quality of the spark. then do the same for the leading plugs. it could be that the engine is flooding. pretty unlikely but an option none the less. when you check your ignition, post yor results and we can go from there.
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Old Dec 17, 2007 | 11:02 AM
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coil

Also clean the coil and coil wires.
WD 40 can help if it is moisture in the high voltage plug or coil areas.
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Old Dec 17, 2007 | 04:51 PM
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I'll try that the next time that I have trouble. Its happened twice since I've had the car (4 months)

I was just assuming it was only firing on the one rotor by the lack of power, and how rough the engine was running.
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Old Dec 26, 2007 | 12:13 AM
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Well, it happened again today (and before I started checking it out more thoroughly it went away, but I managed to get an exhaust clip of when it running like that, if it helps at all

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Old Dec 26, 2007 | 12:42 AM
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Even though the vid clip is short, it doesn't sound like it's running on 1 rotor. Sounds like a fairly normal high idle during cold start. When a rotary is running on only 1 rotor, you will notice a distinct engine shaking. If it's way down on power, it may be losing the leading ignition, temporarily, which indicates a bad connection on the leading side, fouling leading plugs, moisture in the cap or even a bad cap/rotor button.
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Old Dec 26, 2007 | 12:48 AM
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Second video I took is uploaded, this is longer and views the engine, which was shaking a far amount.

and it is quite temporary, usually just when I start the car up, though this time it happened after I had driven it a little ways. It just snowed here, so I figure theres probably water dripping in there somewhere on the ignition, but I'd rather have a second opinion before I start tearing into things.

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Old Dec 26, 2007 | 12:53 AM
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Need better lighting on the engine to see the shaking, but it sounds like ignition. Take a vid of it fully warmed up and off of high idle. When I say shaking, it's like the top of the engine moves back and forth a couple inches or more and is jerky.
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Old Dec 26, 2007 | 12:54 AM
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I will if it does that again, though I'm having some trouble with it idling right now, It seems the car isn't a fan of the colder weather (though its only just around freezing)
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Old Dec 26, 2007 | 11:30 AM
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Yeah sounds like there's something with the ignition. I'd go thru the intire ignition system to find faults. If everything checks out it may be an ignitor ready to kick the bucket
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Old Dec 26, 2007 | 08:08 PM
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+1 on the ignition, How does the Tach respond during this foul running,if it's bouncing around & or moving sluggish that gives you a good idea that it's in the leading,maybe dirty/corroded igniter connections???
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Old Dec 27, 2007 | 12:23 AM
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Originally Posted by cjrx7
+1 on the ignition, How does the Tach respond during this foul running,if it's bouncing around & or moving sluggish that gives you a good idea that it's in the leading,maybe dirty/corroded igniter connections???
Its moving sluggish, but the engine is doing the same.

One thing I noticed when it was doing this, if I revved it up at all and let off the gas, it would hold the higher rpm for a second before starting to drop again.
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