I know, yet another fuel gauge thread. Ive done some searches, and those dont seem to match my issue. Here's my problem: It used to be that the last bar and the first bar were the "biggest"; I could go a gallon or more without showing, and the last bar was similar. I was using 6-7 gallons before the reserve light comes on. Now the gauge drops rapidly. 20 miles is a bar on the gauge, and four gallons gets me halfway. Near the end the rate if decrease with respect to time slows, but I'm not getting what I think is an accurate time before the reserve light (how big is that reserve?). I know the capacity can vary with temperature. We're just getting 95+ here in Texas, but I've been through Texas summers with the car before. The dealership reset the electronics to try to calibrate, with no changed behavior. Now their answer is to replace the whole gas tank + fuel sender assembly. Does this sound right? Thanks!
Edit: I read that TSB. Should resetting the fuel gauge also reset the clock, lifetime MPG, and recent places in the nav?
You can try this to see if it corrects the problem... http://priuschat.com/forums/gen-ii-...5063-fuel-gauge-calibration-instructions.html
If this would be an out-of-pocket repair, ($$$$) is there any chance you can get your hands on a Scangauge II to run through a tank? You can program an X-gauge that tells you what the fuel sender is actually reporting, from 0 to 100%. A comparison between that and the gauge in the cluster might give up a clue. A big mismatch might suggest a calibration issue, or you might see something to indicate a sender problem like not reading 95 or 100% right after you fill the tank. Or, like bisco said, if it's under warranty then let the dealer do their thing.
It's not under warranty anymore. I'm gonna go over to the dealership on Monday and try the recalibration you linked. They did the one in the TSB (I think), but I want to quiz then and see if they checked the resistances and such.