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Venting the G2 tank prior to filling

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by yardman 49, Aug 21, 2009.

  1. cycledrum

    cycledrum PSOCSOASP

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    I fill up at a Shell station with very new looking hose nozzles.

    I just never have a problem at all filling up. I set the nozzle in place and I do not hold the nozzle at all. I let it sit. Pull the handle or trigger, set the holder (can't think of right terms), once it clicks off, that's it, done.

    Based on how many miles on tank, I have an idea how much gas ought to go in. I knew it should be between 7 to 8 gallons. Clicked off at 7.8x. No problem. I could not care less about topping off or maximizing fuel in the tank.

    400+ miles / tank is amazing already.
     
  2. PaulHS

    PaulHS Member

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    Well, today PHriuS needed his fillup. As intended, I followed Ed's method; popped the fuel cap, waited about 4 minutes, pumped very slowly. Unfortunately, there was no measurable improvement in fuel volume. If anything, this fillup was on the low side of average. He took only 8.2 gallons, though I had driven about 20 miles into the last pip, which I don't normally do.

    So, while discouraged, I'm not giving up. Will give the idea a few tanks and try a couple variants.
     
  3. blippo

    blippo New Member

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    I use the slowest setting till it fills up, then fill it one more click
     
  4. PaulHS

    PaulHS Member

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    For those who have posted to this thread that they have no problem filling their fuel tanks, I am very happy, extremely happy for you and I mean no offense. But folks, if it hasn't occurred to you, it is abundantly clear that the vast majority of prius owners have no problem, have only minor difficulties, random difficulties or they rationalize their problem away. So acknowledged.

    Now could you please tell me how your posts are helpful for those of us who do have a problem getting a full tank regularly?

    Like Brett, I can usually estimate how many gallons should fill my tank by my mileage. Rarely, I can pump 10+ gallons into the tank. But typically, it is 6-8 gallons, with coaxing. It is never consistent. I'm looking for a solution.

    Perhaps, Brett, you would care if, instead of the expected 7-8 gallons, your tank would take only 3 to 4 gallons most of the time. Wouldn't that cause you some concern? There are those here on PriusChat who have reported problems that severe. Their problem is not trivial.

    So post away with your accounts of full tanks with never a problem. But could you please explain to me: In the context of this thread, What is your point?
     
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  5. zonie911

    zonie911 Member

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    Paul, I had mentioned my method of filling my tank and it works....but, I had not mentioned in this thread that I had a real problem with filling the tank the first couple of months that I owned the car. I purchased in Nov. and I suppose my short term memory had taken over. LOL
    I had thought that I would see how many miles I would get on a full tank starting from nearly empty.....Bad Idea!
    I had let the tank get down to the last pip and it would only take 3 or 4 gallons, I had to really work over the next several tanks to get the tank stretched back out, which is why I now, never let it go below 1 pip below half empty, before filling up and have no problems now.
    Hope you get this problem worked out too.
     
  6. SageBrush

    SageBrush Senior Member

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    All told in about 5 years owning my Prius I think I have had trouble filling up perhaps 10 times, but not at all for at least the past year, maybe two. Colder weather seemed an obvious association. Usually it was enough to dribble fuel in slowly, but once of twice I just gave up after two or three gallons. The odd thing was that the next fillup was normal.

    I have gotten in the habit of pushing the fuel nozzle slightly into the tank pipe to open the hatch and ? vent the system for a few seconds. I always fill using a slow rate, and do not try to put more fuel in after the first click. Most fillups are when the last pip is flashing, and 9.x gallons in is typical. Sounds almost like a ceremony, eh? Normal people probably think the entire business is quirky, but after five years I just accept that the car has an idiosyncracy or two.
     
  7. PaulHS

    PaulHS Member

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    Thanks, zonie.

    You have an interesting remedy. How many gallons is your typical fillup?

    You have suggested an idea to me. Lately, I've been drawing down the tank to the last pip. I may be better off refilling with two pips left.
     
  8. qbee42

    qbee42 My other car is a boat

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    Reading these posts it becomes obvious that part of the problem is one of expectations. Many posters say something like "only took six to eight gallons." Six to eight gallons is a normal amount for a Gen II Prius. Ten gallons is a freakishly high amount.

    I suspect there is more variability in owners' attitudes than Prius gas tanks. Those of us who quietly accept six to eight gallons say "I've never had any trouble filling the tank on my Prius" while those that don't post about ongoing problems with refueling and elaborate refueling rituals. If we swapped cars it wouldn't change anything. Do you remember the scene from Annie Hall when they were talking to their therapists? Both therapists ask "How often do you have sex?" He replies "Practically never; two to three times a week." She replies "Practically constantly; two to three times a week." Same schedule, different perceptions.

    Tom
     
  9. PaulHS

    PaulHS Member

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    SageBrush, cold weather definitely reduces my tank volume, but contrariwise, I have never been limited to two or three gallons. Even though summer weather is great for mileage and better tank fillups, PHriuS is often still stubborn about the number of gallons he accepts, usually shorting a couple gallons.

    So your solution is almost the opposite of zonie's. I've come to accept 9.x gallons as "minimum satisfactory" fillup even though it's not a true fill. It doesn't happen often enough. And, yes, the entire process is quirky. I once tried opening the rear door and bouncing the car before filling, until I noticed a fellow watching me from the car lot next door. Wonder what he was thinking?
     
  10. PaulHS

    PaulHS Member

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    I take your point, Tom. I'm sure on another thread I agreed with you about expectations. In my post above I categorized those whose expectations are satisfied thusly:

    "...it is abundantly clear that the vast majority of prius owners have no problem, have only minor difficulties, random difficulties or they rationalize their problem away."

    I do disagree with your statement that "six to eight gallons is normal". How did you arrive at that range? Furthermore, if 10+ gallons is freakishly high, then isn't 3/5 gallons freakishly low? That's hardly an issue of unrealistic expectations. That's a real problem.

    There is another aspect to this subject: consistency. If one has driven 500 miles on a tank at 50mpg, he has drawn 10 gallons from the tank. Is it unrealistic to expect that 10 gallons will fit in the tank on the next fillup? Somehow, 10+ gallons got pumped in there on the previous fillup. Given that other factors remain relatively constant, how many 10 gallon fillups does it take before 7-8 gallons is freakishly low for a particular Prius tank?

    Inconsistency is my car's problem. I know by my mpg that I've burned 10 gallons, but I can only pump 6, 7, or 8 back into the tank. Other times it will take 10+ like a sponge. Experience (empirical evidence) has shown me that it will take 10+ gallons. I ask myself, Why won't it take 10 on a regular basis?
     
  11. donee

    donee New Member

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    Hi All,

    Some details left out of the last few posts. If you fill up , what does the gauge say?

    For example, I fill up on the day the gauge falls below 2 bars, .2 of a tank. On a few occaisions this has happened within a few miles of the gas station, and I refilled then. These pumpings were typically about 8.2 gallons. So, that would imply that there is 1.64 gallons left in the tank. Which means the tank capacity is 9.84 gallons.

    My guestimate on this is, I have a 1.16 gallon air bubble (11 gallons - 9.84 gallons of gas I can get into the tank) in my tank.

    BTW. I experienced the freakishly high gas gauge reading on a road trip I did recently. I expected to be at .3 bars after the trip. But, the gauge red .5 bars at the end of the trip. The next time I started up the car, the gauge read .3 bars. So, it seems that to get a good reading on the gauge, you need to stop and restart the car when your doing a long trip.

    A suggestion is please post your estimated air-bubble volume, not how much you tanked up by. As none of us will keep track of what person has what gauge reading during which tanking.
     
  12. qbee42

    qbee42 My other car is a boat

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    "Normal" means of the norm, or conforming to a standard, rule, or average. When I say that six to eight gallons is normal, I mean that most Gen II Prius owners find that they can put six to eight gallons in when they fill up. The word normal does not imply that something is right, correct, proper, or desirable. It only implies that something is of the norm. This figure comes from general discussions on PriusChat, and personal discussions with Gen II owners. It is not the result of a scientific study. The same holds true with the 10 gallon comment. Not many of us regularly manage 10 gallons on a fill-up.

    Three to five gallons is freakishly low, and is indicative of a real problem. That is outside the scope of my assertion. My comment was directed at the perceptions of those of us with Prius operating in the normal range, and how something that is okay with some is bothersome for others.

    Tom
     
  13. john_dough

    john_dough New Member

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    Of course you are correct in saying that a six to eight gallon refuel is not normal in your example. Your sample universe, as mine, is that of all vehicles, not all prius vehicles. In other words, if ten gallons came out of any vehicle's tank, it is "normal" to expect to be able to put 10 gallons back in. Since the prius does not conform to this norm, it is defective (abnormal).
     
  14. zonie911

    zonie911 Member

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    Paul, I never go below 4 pips up from empty, and I usually fill up at about 2 pips below half a tank......and I usually take between 7 and 8 gallons, filling at those pip marks.
    I know my tank may be strange, but that tells me that I really don't have as much gas as you would normally think at 4 pips above empty, and my tank seems to carry most of it's volume at the half mark to the full tank mark.........
    zonie
     
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  15. PaulHS

    PaulHS Member

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    I don't wish to overly belabor this issue, so... just a few comments.

    "Standard" or "rule" requires more precision than can be applied to the subject so I interpreted "normal" as average. Average, however, doesn't always tell the whole story. zonie911, by her description, appears to get 7 to 8 gallons regularly, and is satisfied with the results. Her average is 7.5 gallons. Coincidently, my lifetime average is also 7.5 gallons per fillup. But my range is from 2.4 to 10.8 gallons. I don't see that such variation is cause for celebration.

    Tom, there seems to be a subtle implication in your statement that everyone whose fillups fall within the "normal" range should be, by definition, satisfied with their results. Perhaps my illustration offers sufficient cause for dissatisfaction.
     
  16. qbee42

    qbee42 My other car is a boat

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    My point was that people react differently to the same set of circumstances. If six to eight gallons is what you are going to get, you don't have to be happy with it, but being angry isn't going to change anything, except perhaps your blood pressure. The Gen II gas tank doesn't hold 11.9 gallons, and its capacity varies with temperature, age, and perhaps the phase of the moon. Toyota isn't going to do anything to change that in the Gen II, although they did make a change for the Gen III. Ranting and raving about it is a waste of time.

    Now for those reporting two to three gallons on a fill-up, or something like that, they have a real problem and some expectation of a fix. That's a different story altogether.

    Tom
     
  17. PaulHS

    PaulHS Member

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    Goodness! I hope I don't sound angry, or that I'm ranting and raving! I've just been trying to get a better handle on your original remark. There seemed to be more to it than simply the observation that some owners behave differently than others.

    My point has been that the circumstances may not be as identical as at first glance.
     
  18. qbee42

    qbee42 My other car is a boat

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    Agreed. There are several issues rolled into one when it comes to the Gen II fuel tank and refilling. This topic has been thrashed about so much that some of us are rather sensitive, and at least in my case, I forget who has beaten me up before and is just coming in for another strafing run. A few posters keep beating this dead horse, and it was to them that I was making my comments.

    As to the Gen II fuel tank issue, I break the posters down into four groups:

    1) Those that understand that the fuel tank holds less than 11.9 gallons and have learned to quietly accept it.

    2) Those that understand that the fuel tank holds less than 11.9 gallons, but by god someone is going to pay for it.

    3) Those that don't understand that the fuel tank holds less than 11.9 gallons and are confused.

    4) Those that have a real problem which needs to be fixed.

    With #4 I am talking about people who can only get two or three gallons into the tank, or Prius where refueling is very inconsistent. There are a number of documented cases like this that are indicative of a real problem, not just the normal bladder issue. These people have a good reason to gripe.

    Tom
     
  19. PaulHS

    PaulHS Member

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    Sorry if it seemed I was beating your dead horse. Not intentional.

    I believe my situation is 75% #1 and 25% #4. If I can pump 10 gallons into the tank starting from two pips, then the tank is holding pretty darn close to 11.9 total. Can't be unhappy about that.

    But I get some seriously low tanks as well. I don't mean to sound as if I'm griping. I keep looking for a consistent solution even if it involves the phase of the moon.
     
  20. qbee42

    qbee42 My other car is a boat

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    The only time I have ever been able to put 10 gallons into my Gen II was when it was nearly dry: zero pips and a little farther. I have also experienced pumps clicking off early and repeatedly, but it was always the pump. Typically I fill up at two pips, which usually takes about seven to eight gallons.

    Tom