I just made my worst fuck up

[Dzdimi14]

My car has been sitting for months while ive slowly been doing the timing belt water pump as well as starter motor. I got everything back together and got ready to jump-start the car. I made the classic stupid rookie mistake of jump-starting the car backwards. My stupid sleep-deprived ass attached both cables to my battery and attached to the red on the helper car but ground to bare metal on the helper car. This of course led to my jumper cables melting, my battery frying, but worst of all smoke coming from the engine bay. I immediately disconnected everything and the smoke stopped, however, I can't tell where it's coming from. It seemed like it was coming from underneath the fuse box. I just bought a new battery and the moment I touched the cables the smoke from the engine bay returned and it looked like my radio turned on even though there was no key in the car.

Where do I even start? I doubt this is something I could fix myself since I find electricity to be magic and have no multi meter nor knowledge of how to use one. If I go to a shop Im guessing I will go bankrupt. Is it time for a part out?

Thanks for any help or suggestions as I cry myself to sleep

[Jaxx_]

If you don't feel comfortable using a multi meter, this is your chance to learn. OR purchase a whole body harness and fuse box from another car. Personally I think it would be easier to just buy another car, but this isn't 10 years ago, so I understand why it might be worth trying to save. A shop will probably be astronomical and personally I wouldn't consider it

[roguetoaster]

I don't think this is so hard, at least depending on what you find. Look for melted stuff, open any relays that are suspicious, replace damaged wiring with high quality splices and heat shrink. Clearly, if that stuff doesn't fix it you'll have to learn how to do electrical diagnosis, which is an invaluable skill for this project and for later in life.

[zaq123]

My car has been sitting for months while ive slowly been doing the timing belt water pump as well as starter motor. I got everything back together and got ready to jump-start the car. I made the classic stupid rookie mistake of jump-starting the car backwards. My stupid sleep-deprived ass attached both cables to my battery and attached to the red on the helper car but ground to bare metal on the helper car. This of course led to my jumper cables melting, my battery frying, but worst of all smoke coming from the engine bay. I immediately disconnected everything and the smoke stopped, however, I can't tell where it's coming from. It seemed like it was coming from underneath the fuse box. I just bought a new battery and the moment I touched the cables the smoke from the engine bay returned and it looked like my radio turned on even though there was no key in the car.

Where do I even start? I doubt this is something I could fix myself since I find electricity to be magic and have no multi meter nor knowledge of how to use one. If I go to a shop Im guessing I will go bankrupt. Is it time for a part out?

Thanks for any help or suggestions as I cry myself to sleep

I still don't understand what went wrong? You connected positive to negative? or you just connected negative on the chassis of the helper car instead of the "-" batt. terminal (the correct way to jump start btw)? There is nothing special under the fuse box, just a rubber boot that sends the harness inside the car through the firewall. Not sure of your abilities but E30 harness is pretty simple to navigate (compared to modern cars that is). If you don't know how to use a multimeter and don't understand the basics of a troubleshooting there are not to many choses to get it back on the road: 1)learn 2)pay someone to do the work. In both cases I would imagine that new harness would be required to repair it properly. We all been there as far as doing stupid crap goes. Start by checking all fuses, relays...you can look at the harness wiring inside that rubber boot from inside the car (have to take a few things off to get there).

[66glide]

The ABS relay in the drivers kick panel almost always fries when backward polarity happens. (shit happens)

You said you replaced the starter motor...is it possible you did something weird with the main cable to the starter causing a dead short?

[Dzdimi14]

I still don't understand what went wrong? You connected positive to negative? or you just connected negative on the chassis of the helper car instead of the "-" batt. terminal (the correct way to jump start btw)? There is nothing special under the fuse box, just a rubber boot that sends the harness inside the car through the firewall. Not sure of your abilities but E30 harness is pretty simple to navigate (compared to modern cars that is). If you don't know how to use a multimeter and don't understand the basics of a troubleshooting there are not to many choses to get it back on the road: 1)learn 2)pay someone to do the work. In both cases I would imagine that new harness would be required to repair it properly. We all been there as far as doing stupid crap goes. Start by checking all fuses, relays...you can look at the harness wiring inside that rubber boot from inside the car (have to take a few things off to get there).

I connected both terminals on the dead battery and red to helper car, ground to helper car.

[Dzdimi14]

The ABS relay in the drivers kick panel almost always fries when backward polarity happens. (shit happens)

You said you replaced the starter motor...is it possible you did something weird with the main cable to the starter causing a dead short?

I doubt it, I did accidentally break the green/black wire on the starter and spliced it back but I doubt that has anything to do with it since the car was still working while that wire was broken.

[Dzdimi14]

I don't think this is so hard, at least depending on what you find. Look for melted stuff, open any relays that are suspicious, replace damaged wiring with high quality splices and heat shrink. Clearly, if that stuff doesn't fix it you'll have to learn how to do electrical diagnosis, which is an invaluable skill for this project and for later in life.

Guess its time to spend some quality bonding time with my roomate whos an electrical engineer haha

[Dzdimi14]

If you don't feel comfortable using a multi meter, this is your chance to learn. OR purchase a whole body harness and fuse box from another car. Personally I think it would be easier to just buy another car, but this isn't 10 years ago, so I understand why it might be worth trying to save. A shop will probably be astronomical and personally I wouldn't consider it

Really hope I dont have to end up selling it. This has been my first and only car for the past 7 years :'(

[franklinmomo]

Just came by to say good luck getting it back up and running! I know when I think about doing a job that I haven’t done it is really daunting, but if you do enough research and dive in I’m sure it’ll work out. We’re lucky with these cars because of the awesome community, and because the E30 has been around for ~40 years now I’m sure there are many people who have done the same thing and shared their experiences online. Don’t lose hope, you got this!

[E30tazvertible]

Something similar actually happened to me. Turned the key after putting the harness back in (Original owner made cuts in the harness smh) and POOF smoke everywhere. A solid green wire under the dash went up in smoke. I traced the (solid green) wire thru the fuse box. It was melted beyond saving. So I replaced the wire and any of the other affected wires in the area. It actually wasnt so bad. Get yourself a copy of the Electrical Troubleshooting manual and a power probe/ multi meter. Follow the smoke. Was there any smoke in the cabin or just the fusebox area? If I remember right it was the solid green wire coming off the ignition switch.

[Henizwhoa]

It's been a little over a year. What did you end up doing O.P?

[roguetoaster]

OP quit using the forum seven months ago.

[hopeful]

It sucks to see unfinished posts, especially something like this. I was so committed!

[Dzdimi14]

Dont worry I am still here!
Car is up an running after a year or so of tribulation! I basically started the process of ripping apart all the wiring in the engine bay to see what was melted and what wasn't. The culprit ended up being a result of my own stupidity but not what I had initially thought! My drivers side wheel well plastic was hanging off and the original attachment point was snapped so I screwed in a tac screw right next to the original mounting point. But, in my youthful stupidity ended up drilling straight through the wiring loom leading to the abs. This is what caused my short and fried a bunch of wiring in the car. I followed the wiring from that point down to the battery and replaced all the wires I saw with any sign of melting. This finally got the car running but only two weeks later my starter was getting weak and only intermittently working. Considering I had just replaced the starter (with a shitty knock-off non bosch) I thought the problem still had to be with my wiring debacle. This caused me to spend another 6 or so months replacing bad grounds and whatnot with no avail until I finally bit the bullet and decided to replace the starter again this time with a proper bosch unit. Finally the car runs! Not perfectly though, now I am having a strange problem where my revs start jumping around 1 to 1.5k when coming off throttle which I need to diagnose, but at least I can drive!