Gas still not filling

Are you filling fast or slow? Are you allowing the tank to vent before you add fuel? I don't think a additive will help. How many miles on your Prius?

Also, do you drive conservatively and hypermile? Or do you drive aggressively and drive your Prius like a normal car?

Finally, what type of driving are you doing? Short trips? Stop and Go? Highway? What speeds are you travelling at?

 

A couple of things you can do that might help you.

First, allow the bladder to vent at least one minute before you begin to add fuel. Second, when adding fuel use the slowest setting on the gas nozzle. When the pump clicks off, hang up the pump and be on your way.

Since you are close to 100K, go ahead and do the maintenance for that schedule. Coolant changes on both loops. New air filter for the ICE. Check the throttle body, if it is dirty - CLEAN IT!. Also make certain the MAF is clean. If you clean that, remove it from the throttle body before you clean it. Don't use those spray and pray crap. Use the right stuff and make sure the MAF is NOT in the throttle body when you clean it. Make sure all tires are aired up properly and that your alignment is good. If none of those things help, then consider new spark plugs. When changing the plugs, be certain to use only the Iridium Tipped Plugs. Use the Denso or NGK plug that is made for the Prius.

One other thing came to mind. What's the condition of the 12 volt auxiliary battery? If it is original, chances are it is getting weak and dragging down the mileage too. There is a link in my signature below that can show you how to test the battery on your Prius using the MFD. Run the test and post all three values you see. Run the test after the Prius has set overnight or for at least eight hours of time.

Lots of stuff can affect the MPG on the Prius. It is still a little cool where you are. Once it warms up even more, the bladder will stretch further and allow you to get some more volume out of it. I do understand you are talking about volume, however the above will benefit you in the long run. The bladder is what it is. A additive will NOT change how the bladder works. Some folks have found over time that the bladder tends to shrink a little over time. FWIW, if you ever get a Gen III, you will discover that there is NO bladder in that one. Also, the bladder was only used in the North American Prius. UK Pri and elsewhere do not have it in their Gen II's. How you fill the tank (venting and slow filling) definitely helps but does not completely eliminate the problem.

Remember that the maintenance stuff above does affect the overall performance of the ICE. Don't discount these items IF you are interested in top MPG. Also incorporate "hyper miling" into your driving when possible. That one thing can really raise up the numbers and help to counteract the "bladder" effect.

Best of luck to you,
Ron (dorunron)

 

...the question would be how many gallons to fill it up from empty (~1 PiP). In winter best we get is 7-8 gals and in summer we get 8 to 9 gals. Probably has to be over 60F to see the better filling up. If you're in that range you're OK.

 

The question should be:
How many gallons did it take to fill it.....AND how many miles have you driven since the last fill.

Trying to gauge anything by miles per tankful or dollars per fillup is just not wise.