Electrical nightmare due to jumper cables

[thegawd]

what about the big main plug with the nut on the firewall? did you have a look under/in the terminal block?

 

[TonyMontana214]

what about the big main plug with the nut on the firewall? did you have a look under/in the terminal block?

I unplugged it from the engine bay side but everythng looks normal.
The terminal block is the one that is right in front of the bulkhead connector inside the cab?
If it is then no. I have not looked back there sonce its kn the way

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[thegawd]

under the dash, it comes from the ignition switch.

okay so yours is an 88 manual, i have no idea if this applies or how it could... in an auto theres a pink wire in this loom that powers the tranny. its the trannys only 12V+ lead where the others are switched grounds that operate the solenoids....

this wire starts at the ignition switch, goes to that main plug under the dash on the firewall, to the fuse block on the end of the dash then down and off to the tranny. this wire also supplies the 12V+ for the heated oxygen sensors, if you have those.

of course the info above is from my limited experience while working on my trucks which are vortecs...

Al

 

[sntrym]

If the jumper cables were crossed, then you probably fried something in the starter due to running voltage through it backwards. I would take the big starter wire off the battery and then see if the wires get hot. If they don't, then the problem is in the starter. If they do, then remove the accessory wire that goes across the radiator and see.

 

[AK49BWL]

If the jumper cables were crossed, then you probably fried something in the starter due to running voltage through it backwards. I would take the big starter wire off the battery and then see if the wires get hot. If they don't, then the problem is in the starter. If they do, then remove the accessory wire that goes across the radiator and see.

TBI trucks don't have that radiator wire... They have the junction block on the firewall next to the overflow bottle. And they don't have power to the transmission either lol. The only power to manuals is for the reverse switch.

 

[thegawd]

DUDE! when my starter finally quit on my burb, about 4 months after I replaced the solenoid. it got HOT as hell, like burn your hands hot! this happened close to my dad's house and stranded my wife at a grocery store. when I finally got there I grabbed my dad who diagnosed the truck in 5 seconds, simply by touching the starter. said.... pop the hood and disconnect your battery right now!

Al

 

[thegawd]

good info AK49! I had a 94 burb that's as old of a truck that iv worked on and it seems like so long ago since I had my 1980 malibu but we didnt have to do much work to it.

 

[TonyMontana214]

DUDE! when my starter finally quit on my burb, about 4 months after I replaced the solenoid. it got HOT as hell, like burn your hands hot! this happened close to my dad's house and stranded my wife at a grocery store. when I finally got there I grabbed my dad who diagnosed the truck in 5 seconds, simply by touching the starter. said.... pop the hood and disconnect your battery right now!

Al

We thought the starter was the issue but i swapped it out for a replacement one in my shed.
Same issue.
The solenoid clicks but the engine doesn turn. Meanwhile smaller ground wires get super hot.
If i remove any of those ground wires i lose lights to my instrument cluster.



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[RichLo]

Have you measured the current going through the small ground wires.

And I like the idea of the starter shorting internally, I forgot if you already disconnected all power going to the starter and checking if the small grounds are still getting hot.

 

[PlayingWithTBI]

Did you check your big ground wires/straps, battery to fender, battery to front of engine, engine to frame, back of right head to firewall? It sounds like one or more of those is bad and the only path to ground is through your smaller ground wires.