Bucking broncos--Coupe GT

[Brian Link <bflink@ouray.cudenver.edu>]

    I have an 86 Coupe GT and I got the bucking bronco symptoms also.  I
was going skiing and just filled up.  At first  I thought I bought bad
Gas, but on the way home (night time) I noticed my digital dash would
randomly get very bright then go back to  normal and the coupe had no
power.  "This is going to be expensive".  Well the ground lug on the
intake manifold had one wire hanging on by a thread, the other wire
completely gone.  Well I fixed the wires and the car is back to normal.
What is being grounded to the intake manifold, and how would that effect
my digital dash brightness?  I understand the bucking from the ground
going to mass air flow sensor, but do not understand the dash lights. No
other gauges were effected.