I have a couple of problems for the electrical experts. The gas gauge in my P15 has not worked since I inherited it about 6 years ago. It always reads empty, or less than 1/8, even when the tank is full. I keep track of the miles it is driven, so it is not a huge problem. I just get gas after a certain number of miles. My battery recently died, so I put in a new battery. I noticed the ammeter showed a discharge, even when travelling at 55 mph, so I had the generator rebuilt, and it charges as it should. Here is where it get interesting. I started the car yesterday and let it run at a high idle for a few minutes when I noticed the gas gauge read 1/2! But when I slowed the engine, the gas gauge went back to empty! I played with it a few times just to make sure. At higher rpm's the gas gauge would come up, and at lower rpm's it would go down. The gas gauge is mimicking the ammeter - it just moves slower than the ammeter. The car is 6volt positive ground. Any ideas what could be causing this?