# When do you fill your car's fuel tank? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 10, 2012, 3:20pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086 "2012-08-10T15:20:20Z")\ **Posts on this page:** 17\ **Page:** 3
**Author:** ![Hilarity\_N.Suze](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hilarity_n.suze/32/6223_2.png) [@Hilarity\_N.Suze](https://boards.straightdope.com/u/Hilarity_N.Suze)\ **Post date:** [August 11, 2012, 7:34am UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/41 "2012-08-11T07:34:21Z")
When I’ve got 200 miles. This is a nice easy number to divide things into if I’m calculating my fuel efficiency. Trips: 300 miles or when I need to pee, whichever comes first. Usually they happen about the same time, because I tend to drive kinda fast so this is usually 3½ to 4 hours. ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [August 11, 2012, 7:43am UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/42 "2012-08-11T07:43:59Z")
> [@aceplace57](#): > > I’ve run out of gas a couple times before I turned 20. It’s the hills that will mess you up. That last gallon or two of gas sloshes into a corner and the fuel pump can’t get it. You sputter twice and die. A rare example of a situation in which old carbureted cars really were superior. On those, the fuel the engine was actually using was sitting in the bowl in the carburator and the fuel pump merely refilled the bowl. When the tank was near-empty it was no big deal if the gas sloshed away from the fuel pickup so long as it sloshed back before the bowl ran dry. Of course, running the fuel pump dry wasn’t an issue either. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [August 11, 2012, 11:50am UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/43 "2012-08-11T11:50:48Z")
Many times I travel long distances in areas where gas is expensive, by my home prices are better. So I try to plan around those trips, to have enough gas so I don’t have to fill up in the expensive area. This sometimes means coming back with the light on and the needle on the letter E which is below the line for E. Other times the light is a good indicator for me that it’s time to start considering filling up. ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [August 11, 2012, 11:56am UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/44 "2012-08-11T11:56:17Z")
I fill mine every second week. At that time the tank is about half. ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [August 11, 2012, 11:58am UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/45 "2012-08-11T11:58:00Z")
> [@Procrustus](#): > > I’ve heard it’s bad for the fuel pump if you routinely drive empty. Any truth to that? I heard it was more that all the shit in your tank falls to the bottom so you are sucking that through your system. ---
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [August 11, 2012, 12:01pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/46 "2012-08-11T12:01:12Z")
1/4 tank or a little lower, but I do not fill it all the way up. There is some sort of leak in my vehicle’s fill tube so that if I fill it up until the pump shuts itself off the couple ounces of gas leaks onto the ground. Seems to only happen if the fill tube is all the way full so I just don’t full fill up. ---
**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\ **Post date:** [August 11, 2012, 1:33pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/47 "2012-08-11T13:33:01Z")
Prius - I fill it up when it is one bar or blinking in the summer, in the winter I usually fill it up before it gets to blinking mode. If I’m heading for a trip, I will fill up if I’m under half, esp. since gas is usually cheaper in MN than WI (where I usually travel) Brian ---
**Author:** ![flodnak](https://avatars.discourse-cdn.com/v4/letter/f/838e76/32.png) [@flodnak](https://boards.straightdope.com/u/flodnak)\ **Post date:** [August 11, 2012, 1:37pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/48 "2012-08-11T13:37:29Z")
I answered “1/2 tank”, but what’s more important is that we try to fill it up on Saturday evening or Sunday, which is when the prices are lowest around here. If the price looks especially good one weekend, we’ll top up even if we’ve got 3/4 of a tank. If it gets to 1/2 tank on a weekday, we’ll wait for the weekend if possible. Generally that means we’re filling it up every other weekend during the school year; I’m a teacher and I’m the one who drives to work, while my husband takes the bus. ---
**Author:** ![Raguleader](https://avatars.discourse-cdn.com/v4/letter/r/258eb7/32.png) [@Raguleader](https://boards.straightdope.com/u/Raguleader)\ **Post date:** [August 11, 2012, 2:44pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/49 "2012-08-11T14:44:55Z")
Somewhere around 1/4 tank. Depends on when I remember to go to the gas station, really. ---
**Author:** ![Kenm](https://avatars.discourse-cdn.com/v4/letter/k/bc79bd/32.png) [@Kenm](https://boards.straightdope.com/u/Kenm)\ **Post date:** [August 11, 2012, 3:26pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/50 "2012-08-11T15:26:47Z")
> [@Satchmo](#): > > Anyone know off the top of their heads if a 2001 Cavalier has the pump in the tank? [**This**](http://answers.yahoo.com/question/index?qid=20090419201649AA0fbUg) says the pump is in the gas tank. ---
**Author:** ![interface2x](https://avatars.discourse-cdn.com/v4/letter/i/c0e974/32.png) [@interface2x](https://boards.straightdope.com/u/interface2x)\ **Post date:** [August 11, 2012, 3:29pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/51 "2012-08-11T15:29:48Z")
When the “range” display on my dash says I have less than 50 miles left. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [August 11, 2012, 3:40pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/52 "2012-08-11T15:40:51Z")
> [@Cicero](#): > > I heard it was more that all the shit in your tank falls to the bottom so you are sucking that through your system. You do know that the pickup is at the very bottom of the tank so if you have shit in the rank it would get picked up regardless of the fuel level. Anyway pickups have a filter screen. Don’t sweat it is my advice. ---
**Author:** ![Kenm](https://avatars.discourse-cdn.com/v4/letter/k/bc79bd/32.png) [@Kenm](https://boards.straightdope.com/u/Kenm)\ **Post date:** [August 11, 2012, 3:42pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/53 "2012-08-11T15:42:15Z")
I used to fill it every Monday and/or Thursday, when a local chain discounts the price by 5 cents a litre. Then an Esso station, nowhere near any of the local chain’s stations, began the same deal on Friday through Sunday. So I have more of a choice, depending on my location, four days a week. I’d get an additional three cents off at the Esso if I use a Speed Pass (it links to a credit or debit card), but the privacy disclaimer when registering for it says that Esso will sell my financial information to third parties. There is no info on what the third parties might be, so that might include Richard Nixon’s head in a jar. I’d rather pay the three cents a litre. ---
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [August 12, 2012, 6:42pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/54 "2012-08-12T18:42:39Z")
For me, it depends mainly anymore on the trends seen at GasBuddy. If prices are falling, then I’ll wait til it is almost empty before filling, while if prices are going up I’ll top off fairly frequently. ---
**Author:** ![jabiru](https://avatars.discourse-cdn.com/v4/letter/j/bbce88/32.png) [@jabiru](https://boards.straightdope.com/u/jabiru)\ **Post date:** [August 13, 2012, 9:57am UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/55 "2012-08-13T09:57:01Z")
When the light comes on. Every time I buy a new car, I promise myself that _this time_ I will be utterly vigilant and not let the level get below half full. Sadly, I fail almost immediately. ---
**Author:** ![MegaBee](https://avatars.discourse-cdn.com/v4/letter/m/f0a364/32.png) [@MegaBee](https://boards.straightdope.com/u/MegaBee)\ **Post date:** [August 13, 2012, 2:10pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/56 "2012-08-13T14:10:13Z")
> [@John\_DiFool](#): > > For me, it depends mainly anymore on the trends seen at GasBuddy. If prices are falling, then I’ll wait til it is almost empty before filling, while if prices are going up I’ll top off fairly frequently. This is also what I do, though I didn’t know about GasBuddy. ---
**Author:** ![Who\_me\_1](https://avatars.discourse-cdn.com/v4/letter/w/958977/32.png) [@Who\_me\_1](https://boards.straightdope.com/u/Who_me_1)\ **Post date:** [August 13, 2012, 3:16pm UTC](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086/57 "2012-08-13T15:16:07Z")
I fill mine up depending on my location and where I’m going to be driving in the next couple of days. I work in DC and I’ll never fill up there because it’s usually 20 cents more expensive per gallon in DC. If I have plans to go to New Jersey in the next couple of days, I’ll try to wait to fill up there because it’s cheaper and I can sit in the car and let the attendant pump my gas. [Previous page](https://boards.straightdope.com/t/when-do-you-fill-your-cars-fuel-tank/631086.md?page=2)