93_ZZZZ

So i've looked at a lot of different previous threads but haven't really noticed a common problem among them, all the stories have different problems with the same symptom. I too have a coil that is sparking by the boot of the wire and it appears to be arking from the metal bracket, at night i can see blue in my coil wire and a streak through the coil itself on the left hand top side from front to back along with the constant arking.. however the car still seems to idle and run as if it's fine, except it's wasting alot of fuel and there is a popping sound if i go wot at about 4000-4500 rpms, when it makes this noise the car cuts out.. i'm hoping it has to do with this coil.. I plan on replacing the coil, plugs and wires this weekend... any other suggestions? or thoughts?

Guest47904

Air filter, fuel filter O2s and Cap and rotor should be in the plan as well.

dalynchmob

My bet is that when you change the coil and wires you will most likely find a bad cracked/broken wire. Keep us posted.

hairbear21

It's the coil wire. I had the exact same thing happen to mine when I put on an MSD coil. I don't know how it had happened, but the coil wire that plugs into the coil itself literally turned into dust inside of the boot. I don't know if it was age or what, but I was actually surprised that the car even started!
Replace the coil wire (or better yet, all of the wires) and it will go away.

koolaid_kid

The arcing is a bad thing. Electricity will always follow the path of least resistance. It sounds like there is enough resistance along that path to allow some of the electricity to still go to the coil internals, so it will run, with provisions. The problem with a constant arcing like you are reporting is that it can etch a groove or path there, and when you replace just the wire, the path is still present, so it may still be sought by the electrons.
Were it my car, I would replace both the wire and the coil and you should be good.
The other things mentioned by speedy are good to replace if they are worn or old, but not certain they would be effective for this particular issue.

hairbear21

the coil is definitely getting voltage, it's just that it can disperse it out to the reset of the ignition. What is essentially happening is that the coil is overloaded and creating it's own path out of the coil which is visible as it more than likely is going to a ground.

koolaid_kid

Well, yes and no. The coil's function is to change ~12 volts to ~40000 volts and send it to the Opti. The 12 volts comes in on the 3-connector plug (on my 97, I understand the plugs are different for 93-95s, but the concept is the same). The 40000 volts goes out on the "plug wire" from the coil to the Opti.
The arcing is certainly the electricity going to ground, that is what electricity does. Overloading, however, may be debatable. As I stated, it will find the path of least resistance. If it is easier for the electrons to go across the outside of the coil versus the internal wire, that's what it will do. Why it chose that path, however, must be investigated. Is there a break in the wire from the coil to the Opti, even an intermittent one? Was the wire itself polluted with oil or other engine emissions, which could offer such a path?
I have seen cases where the wires were just low quality, and broke down over time. I have also seen cases where the filth of the engine offered such a path. As to this particular case, only further study and investigation will tell.

Fatdog2

I would first replace the coil wire.Use a gm one.Make sure it does not lean on or touch anything.I ran msd wires,but always ran a gm coil wire(skinny) as the msd wire kept slipping off.Die electric greese .Good luck drilling out the rivits on the coil.I blew up a Accel coil the same day I put it on.I would stay gm on the coil as well.Hope this helps.I finally used a foot long bendable drill bit to do the rivit thing.Whew.

93_ZZZZ

gm coil is the ac delco correct? because that is what i purchased but i can return it if it is not, I also purchased all new wires and plugs. The coil wire is very corroded in the boot, i pulled it off the other day and dust fell out of the boot so that gave me the idea to change everything. Now how many 02 sensors are there and the locations? its 93... if you all don't mind me askin to save some time researching....

Guest47904

There are 2. The part numbers are AC-Delco # AFS21 or gm 19211437 You can also get Standard Engine parts brand since the AC and GM are both made by Standard.

93_ZZZZ

hmmm my box is ACD # D503A Gm# 12498334

Fatdog2

Here is a little help advice thing,that if you do replace the o2's,might spray them first the night before with some =thing to loosen them up.so they can be removed easier the next day.Wd40?Idunno.beer time.Myo2.

Fatdog2

GM coil only.Hope this helps.

Guest47904

You asked how many O2s there are, to which I replied 2 and the part number for the O2's. The numbers you just mentioned are for the coil.

Mikes 1994 z28

I had this problem before and found that I had one bad spark plug. Once I replaced it the arcing stopped. I think the plug was a dud since I had just done plugs and wires 5000 miles previous. The strange part was the engine seemed to run fine. No stumbling at idle or anything