1984's are notorious for having bad wiring harnesses.
Inspect all the wires carefully at the grey 8-pin connector for insulation damage. I just fixed an 84 244GL which had lost ignition power completely- a large white wire thru this plug had grounded out onto the bracket on the intake manifold.

The shorted wire actually parted and burned back a little- of course the car would not run any longer, so it was turned off before a fire started, but that was a real possibility.

The starter solenoid wiring as well as the alternator light wire, oil light wire, and the engine temp sensors, go through this plug.

Inspect for wiring damage here and all under the manifold. Individual wires can be taped to prevent shorting to each other or to ground.

Hopefully that is all, good luck with it!
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Rob Bareiss, New London CT ::: 87 244DL- 249K, 88 245DL- 181K, 84 242DL, 89 244DL parts, SOLD: 86 244, 88 244GL, 87 244, 91 244, 82 245T, 88 744GLE, 86 244