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

Bad coil? Or Bad News?

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Old Dec 1, 2003 | 10:58 PM
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faye x7's Avatar
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Bad coil? Or Bad News?

Tonight I goto start my car and it's running VERY very rough. Warms up while I am inside cuz it's about 30 degrees outside and I get in the car and the tach is really jumping all over the place like crazy. Usually it does this when it's colder, but tonight was real bad. Engine was running very rough as well. I would press the accel and it would kinda bog and then rev. So I tried to rev it up and it would have a hard time getting to 7k and if it got that high it would start sputter and backfire.

So I take it for a drive around the block and she's slow as hell. This was a HUGE difference. So..I think maybe the coil is bad cuz the tach is jumping all over. Plus, I detached the leading coil and started her up and she ran just like she did when I had the leading coil hooked up. So I'm thinking maybe I need new coils?

I really hope I don't need a rebuild. While the engine does have 160k miles on it, I'm just hoping she can last me at least a while longer.
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Old Dec 2, 2003 | 03:24 PM
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I take it I'm right or you all think I'm an ***. heh
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Old Dec 2, 2003 | 03:38 PM
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Could be anyone of the vacuum hoses or selenoids. Im having a similar problem right now and i have new coils.
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Old Dec 2, 2003 | 03:55 PM
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Well, what's an easy way to find out if one of them are leaking or if the selenoid is bad? Why would it just all of a sudden now work?
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Old Dec 2, 2003 | 04:29 PM
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Could be a leak somewhere. Im still trying to find mine. Get a brake bleeder and use it to test the valves to see if they hold vacuum. You can even spray carb cleaners on the lines while its running and if a line is leaking it will run better for a while because the carb cleaner will temp. seal it. Then you know where the leak is. There is also a gose that goes to the air cleaner . Plug that and see if it helps, it leads to one of the seleniods that prevents backfiring.
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Old Dec 2, 2003 | 05:18 PM
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It could also be a bad trailing ignitor. I don't know how the cold weather could affect that, but it's something to check.
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Old Dec 2, 2003 | 07:21 PM
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I've pretty much decided to go with the MSD Blaster coils, anyone know where they got them the cheapest?
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Old Dec 2, 2003 | 08:07 PM
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Check your ignitors first...
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Old Dec 2, 2003 | 08:15 PM
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Yeah, it's a coil or a dead ignitor.
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Old Dec 2, 2003 | 08:34 PM
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Well, ****...haha, Probably need a whole new ignition anyways as it's all original.
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Old Dec 2, 2003 | 09:09 PM
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Ebay for the coils, they go for 30 bucks all the time.

-Marques
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Old Dec 2, 2003 | 10:26 PM
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From: Raleigh,MS
trailing ignighter
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Old Dec 2, 2003 | 10:27 PM
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I can get them at jegs.com for 28.99. Plus I search ebay and only one auction came up.


Now about the ignitors, I've heard they're damn expensive. What part number are they and where do I go about getting them. Other than a junkyard, I live in IL...there are no junk sevens here. I've called before and nobody has a dead seven around.
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Old Dec 2, 2003 | 10:38 PM
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If you buy ignitors new you are looking at over $100 check ebay and local junk yards you can pick them up there for about $25 or less. Hell I got the two extra I have from U-pull-it (a junk yard) for $5 each.
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Old Dec 2, 2003 | 10:55 PM
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which one is the tailing ignitor
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Old Dec 3, 2003 | 12:36 AM
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To all the guys telling her it's the trailing ignitor, she stated in her first post that the car ran the same without the leading coil attached. This means that it's either the leading ignitor or the leading coil.

My money's on the ignitor because the tach signal comes from the trailing and the needle is still moving, albeit erratically. If the trailing ignitor was dead, there would be a small drop in power and no tach.
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Old Dec 3, 2003 | 04:38 AM
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I'm with moses on this one. Sounds like the leading ignitor is bad. Mazdatriz has used ignitors for $90USD if you can't find one on ebay or at a parts yard. You can always post here or on other forums in the Wanted sections and someone may have one or two for sale.

To the person who asked which ignitor is the leading, the leading ignitor faces the radiator and the trailing one faces the alternator. Both are J-109 ignitors on the '81 - '85 models. J-105 are used on the '80 models, I think.
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Old Dec 3, 2003 | 09:54 AM
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By the way, I'm a guy....hopefully I don't come across as a female, while I may seem hyper, I'm no girl. hahaha Faye is the name of my car, so I signed up as Faye x7, but I guess this is understandable as I never really introduced myself about a year ago.

Anyway, this morning I started the car up and she starts just like any morning...then...she starts to die...I've got to really hold the accel so she won't, but then suddenly she goes back up....

So it's like this...starts, revs to 2k...2 seconds later starts to die, very rough...then 3 seconds later it jerks back up to 2.5-3k and is now running fine. So something is obviously wrong...something could be on it's last leg, I wouldn't think it'd be a vacuum leak, would it? Couldn't you hear something like that? Wouldn't that cause a very rough idle only?

Help is appreciated as I'm fairly new to cars, just now getting into them at the early age of 21..heh, and to boot, I'm falling in love with rotaries instead of pistons.

Peace out....
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Old Dec 3, 2003 | 11:41 AM
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Are you saying it's running fine now, or is the cycle you described happening at every startup? I'm getting confused about what the symptoms are.
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Old Dec 3, 2003 | 02:06 PM
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ther trailing isnt out from the sounds, its just lacking
i would try reversing the ignighters and see if that steadies ot the tach
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Old Dec 4, 2003 | 03:11 PM
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My first post was describing what was going on just that one night. My last post was describing another day.

Now today, she ran alright...same as usual.

I dunno, I've got a new coil coming in the mail. I'll try the igniter thing.
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Old Dec 4, 2003 | 05:29 PM
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Have you checked all your plug wires and made sure they are making a good connection and that they are on right?
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Old Dec 4, 2003 | 05:36 PM
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Try the easiest first, new distributor cap?
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Old Dec 4, 2003 | 07:25 PM
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I replaced the cap about a year ago...which would be about...5k miles ago.

Um...Yeah, I'm always checking the plug wires to make sure they're on right and tight.
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Old Dec 5, 2003 | 10:46 PM
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Well, ****....new coil in...battery dies (which I just bought brand new a week ago, Optima Redtop) I think my alternator is dead.

Would a 2nd Gen alt fit in? What about a 3rd gen alt? I see a few on ebay for around 25-50 bucks.
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