My starboard gauges on 08 Lightning ping to 0 every 2 seconds at idle and display erratically under power. Isolated problem to gauges themselves. I switched sides on the AGI boxes and problem moved from starboard to port. Assuming AGI is bad. Boat runs fine. Anyone had this problem? Should I have looked harder for a bad ground or some other problem before ordering a new AGI box?
Thanks-

Check your plugs, and plug wires. Alot of time this occurs when a plug wire is not tight enough.

all too often the problem is farther away than you think it is....I'll check those out and get back with (a hopeful) solution to the problem.....spark plugs could fire once every 2 seconds at idle.....sounds about right......

I replaced the AGI box today. This seems to have solved the problem... At $150+ a pop, I hope that this isn't a routine maintenance problem.... fortunately its just 3 screws and a quick release harness....as my engineering friend pointed out, at 6-800 rpm. spark plugs fire several times per second

Good deal. Glad you got it figured out.