It is very possible that your looking at a failing harness. There is a thread about 140 harness failures but I hate to say it the 124 is just as prone to this problem.
In one week at the local Indy there were three (3) 124's all had wiring harness failures and all exhibited different symptoms. The most common are on the gassers under the hood and across the firewall. This is the result of bad insulation. If I had the harness info I would make looms out of Teflon wire and sell them all over the world
You can check the harness visibly by cutting open the jacket at specific points, its possible you have another problem too just checking the harness is not a bad idea.