When digging up old threads (we call them zombie threads), check the profile of the member you are trying to reach. Their last forum activity is displayed in the upper left corner. Not many seem to know about that. Dojo last posted in 2012 so its unlikely they will get back to you. Some never do.

To answer your question, my guess is the crank sensor is suffering thermal failure as it sits in a hot spot with the exhaust directly beneath it, and the firewall acting like a funnel. The crank sensor overheats and shuts down. Yes, it can affect the gauges. Once it cools down enough, it starts working again. For a while. Before you fire the parts cannon at it, what all have you done? There were a couple posts covering different fixes. CCken posted a brief rundown in post #12. Should you find the crank sensor (or even the cam sensor) needs replaced, buy Mopar. Do not bother with the cheap stuff with the lifetime warranty, as tempting as it is. In my experience, Mopar works better, and lasts a lot longer. Aftermarket uses cheaper, weaker magnets. Some last 5 minutes, some 5 years, some 5 feet. Some are DOA out of the box.

 

I agree with fb97xj1 - very common issue for Auto tranny Jeeps to burn out the CPS. Also extremely common for folks to think they can go with a cheaper replacement than the OEM Mopar part... lots of folks get burned with the cheapos and regret it after correcting their problem with the OEM part.