Fuel Tank fill-up...accuracy?

Sabre66 · 02-28-2004, 06:35 AM

Has anyone else noticed that when they fill their tank (and the pump automatically shuts itself off) it doesn't fill to the "F" line on the gauge in the dash? Or is it just me? I use the same gas station every time, but rarely the same pump each time.

I filled mine up yesterday after 4 days worth of driving (16+ gal) and when i got in the truck the gauge wasn't at the "F" mark. I refilled it and it took another 1.2 gallons. Maybe this is why some of us are getting better than average MPG figures and others aren't. Just a thought.

After this fill-up i took a 250 mile trip back to PA, so as soon as i fill-up this AM i'll post my MPG figure to see what it's at (the gauge shows just a tick below half-a-tank). I'll check to see if the tank actually filled completely this time as well. Have a good weekend ya'll.

Briarman · 02-28-2004, 08:24 AM

hmmmmm...I've tanked mine off twice in the two weeks I've had it and it's always gone up past the full mark on the gauge...I'll check again later this morning as I fill up from half a tank again...gotta hit the open road to somewhere on this gorgeous Saturday morning!

**CaliforniaTitan** · 02-28-2004, 09:22 AM

I never rely on when the pump 'stops' the first time. I always pump more for the reason you stated. After I am done, my gauge is always Full or higher...lol

Chris

lizardking · 02-28-2004, 11:37 AM

Quote:

Originally Posted by Sabre66

Has anyone else noticed that when they fill their tank (and the pump automatically shuts itself off) it doesn't fill to the "F" line on the gauge in the dash? Or is it just me? I use the same gas station every time, but rarely the same pump each time.

I filled mine up yesterday after 4 days worth of driving (16+ gal) and when i got in the truck the gauge wasn't at the "F" mark. I refilled it and it took another 1.2 gallons. Maybe this is why some of us are getting better than average MPG figures and others aren't. Just a thought.

After this fill-up i took a 250 mile trip back to PA, so as soon as i fill-up this AM i'll post my MPG figure to see what it's at (the gauge shows just a tick below half-a-tank). I'll check to see if the tank actually filled completely this time as well. Have a good weekend ya'll.

I filled mine up the other day and it took about 20 miles before it finally reached the full mark...It was really really really slow getting to the full mark..

stevnmd · 02-28-2004, 05:25 PM

Usually, once the pump stops I wait about 10 or 15 seconds, then pump again. There's a lot of air that needs to make its way out of the fill line and tank. Once that air has escaped, I can usually put another gallon in.

sangio · 02-29-2004, 09:22 PM

Quote:

Originally Posted by stevnmd

Usually, once the pump stops I wait about 10 or 15 seconds, then pump again. There's a lot of air that needs to make its way out of the fill line and tank. Once that air has escaped, I can usually put another gallon in.

So this is why I'm gettting 12 mpg! I also let it stop by itself and do not top off. I will try your suggestion next time.

ttz32 · 02-29-2004, 09:25 PM

I never use the fuel tank compacity to calculate the MPG. I use the fuel displacement. ie, if I fill up with 26.23 gallons then I use that because it's a more true measure of how much gas I used.

Quote:

Originally Posted by sangio

So this is why I'm gettting 12 mpg! I also let it stop by itself and do not top off. I will try your suggestion next time.

gtshouse · 02-29-2004, 09:40 PM

I second what ttz32 said. Be sure and fill it up the same each time (if you top it off, top it off every time), then use the actual gallons put in.

Sabre66 · 03-01-2004, 08:37 AM

Thanx ya'll. This is the first vehicle i've had to pump extra to get the line to reach the "F". I've always pumped a little extra to get the price to the nearest $0.10 (a little quirk of mine), but never had to pump as much as a gallon before getting the second click of the pump handle.

Anyways, on my trip back to MD from PA i ended up getting 15.5 MPG @ 269 mi. And that was with 40 miles of 'round town driving before we left.

All's good in Titan land.

dman · 03-01-2004, 09:11 AM

Guys,

You should only fill the tank up until the pump shuts off the first time. If you top it all the way off this is supposedly bad as there is some type of evaporative canister (or something like this) that you can actually damage on newer vehicles. Don't know if this is in the owners manual or not, but I have read this information several times about other newer vehicles I have owned. Plus if the pump shuts off at the same time, each time when you fill up you should still get pretty accurate mileage figures. The only time when this wouldn't be accurate is if you fill up one time and it shuts off with 2 gallons left to go and then the next time you completely top it off. Then you will have inaccurate readings. Hope this makes sense.