Sweet82 Posted November 14, 2005 Share Posted November 14, 2005 As my 01 Forester L was warming up last night, I poped open the hood to see if a headlight plug had worked loose (one headlight was out) and noticed a shocking sight!!! There was small lightning bolts going from the top of my #4 spark plug wire to the "distributor". All the other wires were doing their normal thing but the #4 wire was acting like a plasma globe and sounded like a welder. The kids were terrorified and didn't even want to get in the car after seeing this. As it was dark, late and snowing, I didn't have many options but to drive it back out of the mountains. I also figured that it just didn't start because I happend to look at it. I assume it has been going on for some time now? The car was idling a little eratically, while warming up, which is when I noticed this but ran well the rest of the trip. What I tried: I tried re-seating the #4 wire several times to make sure it was pulged in all the way (top and bottom). I did the same thing on the wire next to it. Results: Didn't change anything. What would cause such an electrical show under my hood? Confused, Glenn 82 SubaruHummer 84 GL 01 Forester L Link to comment Share on other sites More sharing options...
Zephyr Posted November 14, 2005 Share Posted November 14, 2005 Have you tried replacing the wire yet? I have heard of mechanics seeing this effect as a result of bad wire insulation. Link to comment Share on other sites More sharing options...
Cougar Posted November 14, 2005 Share Posted November 14, 2005 The high voltage is seeking the lowest resistance to ground. You might try changing the plug out to see if it is bad or if you can swap the wire for number 4 with another you can see if the problem is the wire itself or the plug. It may be best to change the wire anyways as a 'low resistance path' may have developed through the insulation by now. The fire can be a little scary but it usually isn't a problem and happens fairly commonly. Though if there is a fuel leak near this you can bet other problems will be happening and the fright level goes way up. Link to comment Share on other sites More sharing options...
nipper Posted November 14, 2005 Share Posted November 14, 2005 You have a bad spark plug wire or a hairline crack in the coil tower. This is nothing to be alarmed about and happens on a lot of cars. Just means it times for one of those two to be replaced. It is actually a common way to diagnose a ignition issue. nipper Link to comment Share on other sites More sharing options...
Sweet82 Posted November 14, 2005 Author Share Posted November 14, 2005 Have not tried anything yet, I wanted to try the board first. Didn't want to buy wires or take it to a dealer before the Experts (the Board) had a shot at it. Thanks, Glenn Link to comment Share on other sites More sharing options...
Cougar Posted November 14, 2005 Share Posted November 14, 2005 You should be able to fix this yourself with no problem though the plug may be hard to get at. Link to comment Share on other sites More sharing options...
Sweet82 Posted November 16, 2005 Author Share Posted November 16, 2005 Ok, I go get new wires and get ready to put them on. It's dark and I open the hood and no sparks? What's up with that? I'll probably replace the wires anyway but how come the sparks are gone? Only thing I can think of is when it happened it had been snowing/raining all day and was extremely humid outside but nothing was wet and the car had not been driven that day? Just plain weird:confused: Glenn, 82 SubaruHummer 84 GL 01 FrankenForester Wire prices... Pepboys $82.00 Checker $40.00 but they don't have any Dealer $44.00 for OEM:D Link to comment Share on other sites More sharing options...
cookie Posted November 16, 2005 Share Posted November 16, 2005 They only do it when wet. This is also why you replace the wires on a regular basis. When a wire goes bad it can arc and take out a coil too. Link to comment Share on other sites More sharing options...
Cougar Posted November 16, 2005 Share Posted November 16, 2005 You are correct about the moisture in the air. Spraying a light mist of water from a spray bottle over the ignition area can help show up these kind of problems. Since you are replacing the wires, I would recommend you replace the plugs also at the same time. Ok, I go get new wires and get ready to put them on. It's dark and I open the hood and no sparks? What's up with that? I'll probably replace the wires anyway but how come the sparks are gone? Only thing I can think of is when it happened it had been snowing/raining all day and was extremely humid outside but nothing was wet and the car had not been driven that day? Just plain weird:confused: Glenn, 82 SubaruHummer 84 GL 01 FrankenForester Wire prices... Pepboys $82.00 Checker $40.00 but they don't have any Dealer $44.00 for OEM:D Link to comment Share on other sites More sharing options...
cookie Posted November 16, 2005 Share Posted November 16, 2005 and coil if I found any damage. The arc can easily damage both. I am going to do this on my own car soon even though it runs perfectly as PM. Link to comment Share on other sites More sharing options...
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