OK, lets clear a few things up; I haul gas for a living. To SOME extent, depending on WHERE you live, all grades of gas ARE made at one refinery. But here in south Louisiana, I haul gas from eight different racks ( there's a difference here, between racks and refineries) SOME racks, get their product from several different refineries and by a long shot, not ALL regular and premium gas is the same. Chevron's premium is by far, THE best gas money can buy. I know just from hands on experience handling and using the stuff. Regular gas also varies greatly in quality, I can tell this from the various colors of the stuff, depending on where I pick it up from. Here in south louisiana, I haul from ten different refineries, and their gas is not all the same. I also haul from one RACK which is located at the junction of two piplines,which originate in the Houston Tx. area, so there's no telling how many refineries supply this one rack and certainly not all the regular gas there is the same. One of these pipelines runs all the way up to New Jersey and supplies numerous racks along it's length. So these racks are also supplied by more than one refinery. As for those who think Chevron's advertising is BS, I have a lawn mower that certainly knows better. After running several tanks of the "cheap" stuff in it, it starts to run like crap. At that time I pour in a tank of Chevron premium and after mowing my two acre yard, it's back to normal again. Techron DOES work, I've had this happen numerous times to know what I'm talking about. Texaco and Shell also use Techron in their premium. And it's also present in their midgrade gas too. Midgrade is the oil companies money maker. Generally the price at the pump is a ten cents difference between regular(87 octane) & midgrade and also between mid to premium ( 93 octane). But midgrade (89 octane) is made by mixing 35% premium to 65% regular. The ten cent price spread reflects a 50/50 mix though, if you mixed it in your tank by pumping half and half ( reg. & prem.) you'd get 90 octane gas. As for the electrical problem in the tank sender, I think it's just that, an electrical problem, I doubt it's caused by the gas in the tank, but it still could be. elcetrical problems such as this can have some strange causes and just as well have some strange fixes.