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mattmattyxcore 02-23-2013 01:41 PM

Coil Pack Throwing Sparks!
Anybody else experience this issue? I started up my legacy today and it was running really rough and I noticed that sparks were coming from the base of the spark plug boot to the metal edges of the coil pack. I am just going to replace the coil pack since I'm willing to bet it's original and has 240k miles. I also replaced the plug wires last year so I know they are good and all connections are secure. I haven't done any repairs or changed any components lately so I don't know what could be causing the sudden failure aside from old age. Any thoughts?

DOHCEJ22E1 02-23-2013 02:06 PM

Coil packs go bad & crack ever so slightly after a while so they are prone to throwing sparks. Powerful sparks. Hard enough to bite the living s**t out of you. I hate old coil packs. I threw mine away once it bit me. If your coil pack is throwing sparks, replace it immediately.

mattmattyxcore 02-23-2013 02:15 PM

Yeah unfortunately it got me too when I went to attempt to snug up the boots, lol not fun! :icon_surp

SBT 02-23-2013 02:48 PM

Probably due to carbon on both the end of the wire and the CP tip itself. Dremel-tool both sides of the equation and put some dilectric grease on the CP tip and inside the wire and that should fix your arcing issue. This presumes that both the wire and the CP test-out for proper continuity specs.

pleaidestar 02-23-2013 03:13 PM

Time to upgrade to an msd 8239?... you will enjoy a smoother idle and better fuel efficiency

mattmattyxcore 02-23-2013 04:58 PM

After a bit of research, I think I have found a better alternative to the MSD.
Accel make a female terminal ignition coil at ten dollars cheaper. So instead of buying new wires or terminals and modifying them I could just get this one, right?

pleaidestar 02-24-2013 12:39 AM

I don't see why not...look exactly the same as the msd piece, I would get new wires still, of course subjectively if you have thin stock diameter wires. Won't be a problem with them but new wires will complete the upgrade.

spooln30 02-24-2013 01:27 AM

While your at it there's a thread about running a non-resistor style spark plug and low resistance wires that are supposed to improve fuel mileage and get a more efficient engine. Read up on it, it maybe worth it.

itzed 02-24-2013 01:20 PM

Just yesterday, I had the exact same problem on my 2006 2.5i (145K). Mine started sparking to a metal ground from the coil where #2 cylinder plug wire plugged into it. It threw a CEL and the code was #2 cylinder misfire. Today I disconnected the battery and tried to get the plug wire off the coil, and the sucker was basically welded on to it. I ended up destroying the plug wire and the metal part of it stayed inside the coil. I tried to pull it out with pliers, and no way it was coming out - it ended up breaking off. So I just ordered a new coil and new set of plug wires. I was looking for a DIY when I found this thread, and after reading this, it sounds like it was more likely the coil anyway, so a new coil and set of wires every 145K I guess is nothing to complain about. Anybody know of a walkthru? I'm just wondering how much junk I need to remove to get to it.

mattmattyxcore 02-26-2013 05:02 PM

Replacing the coil itself is amazingly simple. Just unscrew the four bolts holding it down after disconnecting the wires. (Don't forget where they go) and swap in the new. There are a ton of threads about how to do the MSD swap and even that is simple, just costs more.
I ended up just going to the junk yard and snatching another coil from an EJ22E and grabbed a few minor things for both of my cars and it only cost me $12. I just bought the Speedyracer UEL Headers and the mortgage is due so no money in the budget to test out the Accel coil, hopefully some other time.

itzed 02-28-2013 02:45 AM

I did this last night, the coil and the wires. It took me about an hour because I wanted to make sure I was careful, and didn't want to bend the new wires too much. Everything went well, and problem was cured. I did end up removing the flexible part of the air inlet for better access, but that was no big deal since the air box had to come out anyway to reach the plugs. One thing I did struggle with a little was the plastic wire clip that plugs into the coil. There is not much slack on that wire, so you have to work on it while the coil is partially down under the manifold. I had a hard time getting the clip off. I eventually carefully pried it off little by little with a flathead screwdriver, making sure I didn't break it. When putting it back on the new one, it was also a pain, and never really snapped. I'm not sure it's locked on, but I don't think it's going anywhere. I guess all the heat from the engine does a number on it.

mattmattyxcore 02-28-2013 04:28 AM

Yeah that clip is designed great as far as staying connected but when it comes to removing it, major PITA. I had a very small flat head as well and it took me a while to get it apart. Put some zip-ties on it or some electrical tape/shrink wrap if you bust the clips on the engine side connector.

SBT 02-28-2013 06:50 AM

If you heat the plug/clip area a bit with a hair dryer, or a heat gun on a lower setting so it doesn't melt the plastic bits, that will also heat any imbedded grease or oil, and make it easier to 1) compress the clip and 2) slide the plug off the connection.

It's a PITA location, but the heat does help going off and putting back on.

monkeyposeur 03-01-2013 09:08 PM

2 Attachment(s)
matty, is your LS w/4EAT or 5MT? The respective coil packs are different from the factory. The 4EAT is a Hitachi and the 5MT is a Diamond. The Diamond coil packs are a good upgrade to put on the 4EATs.

It's always a good idea to test the resistance of the primary and secondary coils to see if it is within FSM specs. When I replaced the coil packs on both of my subies I combed through (tested w/multimeter) a lot of coil packs at the junk yard to find a few really nice ones. I agree with you that the clip can be a pita the first time you try to disconnect it but after disconnecting a dozen or so it gets really easy. Flathead screwdriver is the way to go. Junk yards are a good place to learn how to take things apart. If you break it move on to the next one, lol.

Here are two pages from the FSM regarding coil pack specs.

mattmattyxcore 03-02-2013 05:56 PM

Funny thing is, I have a 4EAT and the old coil was a Diamond. The one I grabbed at the yard looks practically brand new but had no markings.

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