[RIP]

Welcome to the forum. You have a fairly common problem found on many posts throughout the forum. Because you can beat on the dash (a common tool) and get the gauges to come to life you probably have a bad solder joint on the circuit board in the instrument cluster or a bad connection at the cluster connector. A less likely possiblity is a faulty body control module better known as the BCM. You can try resetting it by pulling the IOD fuse located in the fuse/relay panel next to the battery. Leave it out for a minute or so then reinstall it. Use the search function at upper right above the advert for more info.