(1987 fc non turbo)I was wiring a switch for my radiator fan because the owner prior had the fan directly to the battery(he would disconnect the negative terminal when he wasn’t driving) I have no idea what I’m doing when it comes to wiring and the wires got red hot, after a few seconds I disconnected the battery. The fan is now wired back the original way and is not an issue. The issue at hand now is that the car will struggle to start, and if it does start it will die down after a few seconds. I replaced the battery and all the fuses since so I know that is not the issue. Can someone help me diagnose if this is a wiring harness issue, fuel sensor issue, etc… I’m really not sure what I messed up when those wires were burning.

 

welcome to the board.

when you say "die down", are you saying that it stalls out completely or is it simply dropping to very low RPM?
you're going to have to figure out exactly which circuits were affected by your mishap. it would probably help if you described what exactly you did when it occurred. where and how are the wires for this fan being run? i know you mentioned not being good at wiring, so photos might help you get better help in addition to whatever narrative you type.

on a side note, just as a general rule, when adding electronic equipment to your car, you need to include a fuse (and maybe even a relay) into whatever circuit you create. another tip, which is more my personal preference while others may disagree, is i try not to "tap" into OEM circuits as much as i can. a stand alone circuit can't cause havoc that may implicate or affect an OEM circuit. just 2 cents there.

 

by die down I mean it will completely shut off, while it’s on for a few second I try and give it gas. The rpm’s will rise and then when it shuts off it’s as I let my foot off even though I haven’t. To go into more detail about what happened. I had wires going through where the wiring harness goes from the engine bay to the passenger side, down under the glove compartment and then behind where the radio used to be which is now just a metal panel because the previous owner did a radio delete. So there was definitely contact with some other wires, however I saw no damage visibly. I also can’t see everything it was touching however. So I did have fuses on each three wires, one going to pos of battery, one going to neg of battery, and one going to the fan. I knew one of these lines shouldn’t have a fuse but I didn’t know which so when I started guessing and taking out fuses is where I messed up. The wires started to melt and when I pulled the wires off the switch, I saw one of the wires was red hot, smoking, etc… I then disconnected the battery to stop what was happening. Again, I’ve reconnected the fan how it was and I’ll deal with that another time, I’d just like to figure out if my problem is with a sensor, or wiring in general. Or is anyone has any a suggestion of who I should ask, as I’d rather not spend a lot of money on getting the issue diagnosed at a shop unless unavoidable.