Fuel gauge reads empty but tank is full?

[CrimsonBrian]

Hey guys,
Today while I was driving on the highway, my car all of a sudden dinged at me saying I had no gas (the little orange light went on too). I thought this was odd since I had at least a 1/4 tank last I had checked. I pulled over to the gas station and was only able to put 2 gallons in before gas came pouring out. I continued to run all my errands and drive probably another 20 miles or so without the gas gauge lifting off of empty. It has been really cold here in Boston, might it be possible that the gas that was in the tank froze into some huge ice cube? If I can remember back to my high school chemistry, I though gas froze at a really low temp because it has alcohol or ethenol in it. Is this true? Or is my gauge just totally retarded? When I look at the trip computer, the Range button lists all kinds of different readings from like 400+ miles to four dashes. Any help would be super appreciated! Thanks!

Brian

[theonew]

Most likely your fuel level sender is screwed up. This happened to me last winter but the cause of the failure was even more distressing. In my case somehow a breather line froze and the force of the fuel pump was strong enough to implode the fuel tank, when I looked at the bottom of the fuel tank it had a concave dent running almost the whole width of the tank. The collapsing of the tank was enough to ruin the fuel level sender inside the tank. I urge you to look at the bottom of your fuel tank to see if a similar thing has happened to you.

[CrimsonBrian]

Oh great, I'll take a look at that in the morning. If you dont mind my asking, how much was this to repair?

[shogun]

You can repair the fuel sender. Just visit my website and look for the link to Johan and Sean.
Sometimes cleaning it is enough.

[theonew]

I bought a tank from a salvage yard for $100 plus I had to pay $100 to have it shipped, Fed Ex or UPS won't handle fuel tanks. And I paid an indie mechanic $200 to install it, but honestly if I had to do it again I would just spring for a new tank. The salvage tank I got had some odd problems and was hard to install because the filler neck had been bent, either during shipping or removal. I believe a new tank is around $400.

[CrimsonBrian]

OK, I just went out and looked at my tank and it has totally collapsed. I guess I will be taking it to the mechanic tomorrow, which will be awesomely expensive, I'm sure. Aside from the tank, what else will I need to have replace? Thanks for the help guys!

[theonew]

Sorry, I had a feeling about that. It was really cold when it happened to me last winter. Though it was and still is a mystery to me where the freezing ocurred that caused the problem, I opted to replace the charcoal evaporator canister, which was only about $20, and also got a new fuel filter, just for general maintenance purposes. The salvage tank I got came with the fuel level sender in it, but if you get a new tank you will need to get a new one as I'm sure the one in your tank is toast. I drove my car for a couple of weeks while waiting for the tank to come in, and found that the tank capacity was less than half the original capacity. Be careful and fill up often if you drive it at all like this.

[CrimsonBrian]

I guess as long as I have them down there, I'll replace whatever needs to be done. Is there some way to prevent this? I mean, it happened well after the car had warmed up, although it was probably in the low teens when I was driving it. I am not aching for this to happen a second time! :)

[theonew]

I wish I had a clear answer for you. I have checked all the lines in the fuel system for blockages but other than that I'm just hoping it was a really rare occurrence.

[theonew]

My mechanic thought it was most likely a problem with the charcoal evaporator canister. Perhaps it was already a bit clogged and had accumulated moisture which froze and that was the reason I changed it. And this winter I have driven the car on some really cold days and it has been fine, knock on burlwood.

[CrimsonBrian]

Thanks so much, I'll have them replace it as well. I'll let you know what the total damage is. I swear, money in, money out!

[theonew]

Just to compare notes, in your first post you said you had about a 1/4 tank when this happened and I had a little less than that when it happened to me. Perhaps it has something to do with the cold weather and the small amount of fuel.

[Kalevera]

When the temps get low, it's a good idea to keep the tank at least 1/2 full as condensation can build up in there.

Actually, I was talking about this with my family recently. Apparently, someone in my family was talking with a "garrulous redneck" while waiting in line at the post office or the bank or somewhere. The fellow mentioned that it's not a good idea to buy gas at a station while a tanker is...uh....filling the tanks, because they'll be full of condensation from being at low levels and you'll be paying for more water. I guess it makes sense.

best, whit

[CrimsonBrian]

Yeah, I had a little less than a 1/4 tank. I initally thought that the small amount of gas had frozen. If having too little gas is the problem I will be filling up every 500 meters from now on!

[theonew]

one of my stubborn fuzzy-logic idiosyncracies has been to only fill up my tank when it is near empty, the 'idea' being that the more gas the greater the weight the less mpgs and as well as more time spent stopping to fill the tank. well whatever time and money I saved over the last 20 years surely couldn't have paid for that costly repair.

[CrimsonBrian]

Hahaha, I try and run my tank to nearly empty more to just see how far I can go. I get all confused if that trip odometer is at 500 and the tank is 3/4 full. From now on, my tank will always runneth over during the winter, which thankfully runs only from September thru June in Massachusetts.

[theonew]

one time, soon after I had just gotten my license I was driving with my mother when my car ran out of gas. We were at the top of a long, winding hill and I was able to coast the car for just over two miles into town, while my mother was yelling at me, and rolled to a stop right next to a gas pump at the only service station in town. I was like, 'See Mom, no problem'.

[CrimsonBrian]

Nice work, I had that happen once in a loaner car (an old 2002 that got like 30 bazillion miles to the gallon). I was on the highway and managed to exit and roll to a gas station off several blocks off the highway. I am not eager to try that again! :)

[theonew]

I once had a VW Diesel and when it got low on fuel it would stall but you could start it again and drive for a few miles before it stalled again, and then you could start it and drive a few more miles before it would stall, and you could keep doing this while the distances kept getting shorter and shorter. though it was usually enough to get you to the nearest filling station, there was no guarantee that the station would have diesel fuel. I sweated that a few times.

[CrimsonBrian]

Alrighty, I just got back from the mechanic, the damage was $913.72 ($421 for the tank, $149 for the sender). The gas tank was a total mess, it looked like a pancake and the sender was in a billion pieces. My mechanic says I am lucky I didnt go up like a Roman candle. I guess the lesson is, keep the tank over half in the winter to prevent the build up of fumes!