Firstfives.org

So, I've been having lots of intermittent problems with my car, and slowly I'm tracking them down one by one. The most recent involved the wiring harness to the engine from the fuse box- as it turns out, it passes right by the ground by the oil filter along the engine. The wires were melted through, and the black wire leading to the ignition coil/condenser was causing a short. I can't believe this is not a more common problem! I don't know why theyd snake the wire down there.

Anyways, SO, I took the harness apart, I checked all the wires with an voltmeter, I put everything back together and went for a drive on the highway.

The car cut out on me twice, and I had to start it in neutral as I was rolling along.

When I got to the muffler shop to take those reactors off, I noticed that my clear ignition wire was now fried after my ride. I also noticed the brown wire leading to the top of the STARTER had slipped off.

I am stumped as to why this wire is fried!

I have checked for inter-connectivity between in the harness itself, but nothing came up with a voltmeter.

I have narrowed it down to:
A) something to do with the wire to the starter not being connected causing an overload of sorts on the resistive wire. but how?
B) something messed up in the fusebox when i jammed the box back down ... I noticed there is some connectivity between the pins on the fusebox when I check the voltmeter, is this normal??? (same things with the 'pins' in the diagnostic socket)
C) a bad ignition coil somehow giving me grief.
----------> If anybody has any ideas as to why it fried, please share with me!! I am under the impression that only + and - together can cause a wire to fry, not a + alone.
OR
D) my car is just running much better than before and so the resistive wire is just old and cant take it so it melted. LOL

Aside from this mystery frying, I also need to rebuild this set of wires but
As I understand from reading this forum and 2002 forums, that transparent wire is a resistive wire, about .9 ohm or something like that.
Now I need to remake this harness from scratch, do I add in a regular wire instead of this resistive wire? I think this resistive wire is there so that the points won't wear out. Make sense? Should I just switch my coil out anyways? I'm getting a yellowish spark at the distributor.

What kind of coil? I haven't read much here about coils.
On bavauto there are two kinds- a black and a blue.
What to get???

Any thoughts appreciated!

You need a resistor in there of some type. Many cars and later E12s, 528i's, used a conventional ballast resistor. I would try to plumb one of them in before trying to figure out a replacement transparent wire resistor. See #11 here.



The wire that runs to the starter is supposed to give you more voltage for starting, I'm not sure how important it really is, but on older cars it had been done like that forever. On coils, the blue ones were supposed to be better, but I'm not sure it really makes much difference. I'd go thru points and condenser before getting a new coil though, and look at other places like Autohausaz and Blunttech for parts, they're often much more competitive on pricing.

Interesting.

I read on the 2002 forums the guys just use 18 AWG wire,
but I think that will wear out the points faster from what I understand.

I made a whole new harness, without a resistor, the car seems to have more "umph"

But I think I will put in a ballast resistor so I don't have to change my points much sooner than later.

I've also heard of coils overheating due to bad ballast resistors, though never seen it myself. If point life is the only issue I'd still do it, point life isn't all that great anyway.

I ordered the ballast resistor listed on one of those sites for my car.

Thank you!