'86 2.8 Electrical System Intermittent

[xxmetal]

Howdy all! Hope y'all might be able to help orient me with this  *nearly* catastrophic electrical failure I am having. Just bought my '86 on Sunday, and began experiencing issues with the electronics on Monday night. No issues the whole time I was test driving, or driving the two hours home. Since then, this issue has been presenting itself maybe 80% of the time I have spent driving.

 

Complete loss of non-engine electrical systems. No radio, no lights (internal or external), no gauges, no heat/AC, no horn.

 

But the car starts right up no problem, and continues to drive no problem. When running, battery measured at 14.2 V post to post, crossing off a battery/alternator problem. No blown fuses that I could find.

 

When the issue somewhat corrects itself, I have seen 2 conditions:

1. Full system functionality. Everything works as it should

2. The radio and gauges turn on. If any other power is requested (turning on headlights/gauge lights, or turning on heat/AC) the whole system shuts down again

 

Where should I start? I don't want to disturb the engine, it seems to be working perfectly. I have ordered the 1986 electrical manual from Ebay, so I probably won't be able to do any unassisted wire-chasing until it arrives. Is this a common issue?

 

Thank you!

[cruiser54]

Burned brown wire at ignition switch. Switch likely toast. 

 

 

[eaglescout526]

Grounds too! Check and clean all grounds. Chances are the original owner probably didn’t do a damn thing to them.