I have the Same Problem
1993SSP said:
Ok, here's my question! I was cranking my car after engine swap tonight, while trying to get the car started smoke started coming from near the battery, the small wire that runs off the battery ground over to the inside fender wall freakin melted the covering off?!?!?! Any insight on what caused this? The main ground wire is still perfect. Also I noticed that sometime in the past the covering on the wire to the fuseable link for the fuel pump has been extremely hot and melted in the past (from a previous owner) and has been spliced together, anyone know what could cause these problems? The last thing I'd want is a electrical fire. Any pointers are appreciated.
I have the same problem as you. And I think replacing the Ground AND starter cables IS the solution. Mine is an 1986 5.0 LX. I pulled up the wiring diagrams from ALLDATA (nifty online subscription). Heres what the wiring Diagram tells me.
The 10 ga. wire that comes off the Battery (small one) goes to Ground G116.
Then it goes to Connector C149 (about 12 inches after the spot screwed to the fender).
After C149 the wire turns from black to Blk/Lt. Green. Then proceeds to Splice S131(In harness near connector to battery). From there it splits (inside the plastic tubing) and goes to pin 40 & 60 on a Solid state gizo, as well as to the EEC (electronic Engine Controll), fog lamps, EEC power relay, and Left & Right Heated EGO Sensors. The EEC basically controls every sensor and gizmo on the engine.
So what is hapening, is one of two scenarios:
1. The Big RED cable going from the starter solenoid to the starter, is chaffed and overloading the little 10 ga. wire.
2. The Big Black Cable going from the negative terminal on the battery to the engine block, is corroded. The result is Every electrical gizmo on the car is grounding through the litttle cable instead of the big thick cable.
I'm going with senario #2. Otherwise The Whole wire all the way up to the ECM would have melted, instead of just the portion that went from the fender to the battery terminal.
I Hope this helps everyone that has this problem.