Tmurch

This is an on again off again issue. At times everything fine. Starts and runs good. Other times when ignition turned on, dash lights blinking, gauge needles jumping. Crank but no start. Clean and charge battery. Ground connections. Check wires from main fuse panel under the hood. Wires go to 3 junction blocks on firewall. Took those off looking for corrosion. All good. Any help would be appreciated. Thanks. Tom

The lights you see are blinking rapidly and the gauges are jumping about it half an inch