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Failing coil?

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Old 03-25-2012, 04:32 AM
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azbanks
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Default Failing coil?

My S2 is acting up.
It has been loosing power while driving. I pulled up to a stop sign right near my house the other day and it just died. It will at times just lose power for a second or two. Other times it dies out for 10-30 seconds. If it dies and comes to a stop, It will restart if I let it sit for 10-15 minutes.

I've got fuel pressure. At first I was wondering if I had a plugged cat or if I had a failing TPS.

In doing some diagnosing, I pulled the coil wire off the distributor and laid the tip near a ground source. I had my son watch it while I cranked over the motor. He saw "little sparks". My next test was to put the coil wire back on and pull one of the spark plug wires. It fired right up. It fired right up no matter which one of the spark plug wires I pull. I can plug the wire back in and it will run on all four cylinders for a while before dying.

Is my coil starting to fail or could it be something else?

Last edited by azbanks; 03-29-2012 at 04:25 AM.
Old 03-25-2012, 05:18 AM
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pettybird
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I have an S and not an S2, but I'm pretty sure we both have an ignition module below the driver side headlight and coolant reservoir...if that heats up significantly it can fail.
Old 03-25-2012, 08:17 AM
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Fara
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I had the same problem, only mine would die randomly and I'd lose instruments

Turned out mine was a combination of an alternator on it's last legs and a loose battery terminal.
Old 03-25-2012, 01:34 PM
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azbanks
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Originally Posted by pettybird
I have an S and not an S2, but I'm pretty sure we both have an ignition module below the driver side headlight and coolant reservoir...if that heats up significantly it can fail.

Would it give the same behavior of running on three cylinders when it was failing?

Originally Posted by Fara
I had the same problem, only mine would die randomly and I'd lose instruments

Turned out mine was a combination of an alternator on it's last legs and a loose battery terminal.
Did your car have the same three cylinder behavior?
Old 03-29-2012, 04:26 AM
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azbanks
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Is there an easy way to get the coil out without removing the washer tank or the headlight motor?
Old 03-29-2012, 12:19 PM
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pettybird
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yes--loosen the clamp for the power steering reservoir enough until you can get it out of its bracket, and then it's a clear shot.

a faulty ignition module will overheat and cause misfires. this happens a LOT on 80's and 90's domestic cars. it should be pretty hot to the touch when it's screwing up if you can catch it.

A coil can do that, as well, with the same heat issue...
Old 03-29-2012, 12:51 PM
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azbanks
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My car died at the stop sign that is about 100 yards from my house. I would be really surprised if the ignition module got hot in a 100 yard drive.

Also, would the failed ignition module kill the entire ignition or would it allow the car to run on three cylinders?
Old 03-29-2012, 04:06 PM
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968 GUY
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Could it be the DME relay?
When mine started going bad, it would shut down, then start again after a bit.
Old 03-29-2012, 04:11 PM
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kingston944
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I had an issue the car would be running fine the just turn off . My issue was I believe to be a dirty connection on the bottoms side of the fuse box. I replaced my fuse box with a used one and cleaned the contacts and have not had any trouble since I believe if had only cleaned the contacts I would not have had to replace the box. Good luck let us know how you make out .
Old 03-29-2012, 10:16 PM
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azbanks
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I have two new DME relays in my glove box. I tried them both and neither one fixed the problem.

I replaced the coil and the problem appears to be gone.
Old 04-01-2012, 07:34 PM
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kingston944
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Great hope you have your issue dealt with .



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