Fuel meter reading

[zamboni]

How can you tell if the meter reading is accurate?

[fullboost]

How many miles to you get on a tank. when you've gone 1/2 that distance does your tank read about half. Also, i believe the low fuel light comes on with 2 gallons left and should read between an eighth and quarter tank.

[hatepotholez]

Originally Posted by zamboni

How can you tell if the meter reading is accurate?

Good question. Currently filled up the tank and going to see how many miles I get through a full tank.

I also read somewhere on the older Bmw's you can do a instrument cluster test for actual fuel levels.

[centexE9x]

Originally Posted by hatepotholez

Good question. Currently filled up the tank and going to see how many miles I get through a full tank.

I also read somewhere on the older Bmw's you can do a instrument cluster test for actual fuel levels.

You can read the est. liters of fuel in the tank. Best bet is to fill it and see if the amount of fuel the cluster shows in the tank agrees with the capacity. Also wouldn't hurt to check it when very low to see the the driver side of the tank is reading empty when it should.

[zamboni]

My average is 245 miles per tank and max is 300 to LA.

[crystaweizen]

Originally Posted by zamboni

My average is 245 miles per tank and max is 300 to LA.

In an e82? Or e92..

[dorkdog]

I have had fuel quantity on my tablet thru OBD as percentage remaining/miles remaining. Knowing electronics as I do, the issue is, if the tank is not square, a simple potentiometer-based float will not give accurate results, unless the eccentricity of the tank is programmed into the A/D conversion as a variable based on a change in surface area over any given fuel elevation ('delta-y) in the tank.

One would have to vent fuel from the tank at a constant volumetric rate and look for a straight line as plotted by fuel remining data points, adding positive pressure to maintain fuel flow at a constant rate despite an decrease in gravitometric pressure as the fuel quantity weakens.

One could also take data points at small intervals, perhaps 0.1 gallons, and plot the 'fuel remaining' points, looking again for linearity.

If it's linear with linear depletion, it's likely accurate.

[dtwyim]

I know gas station fuel pump might not be the most accurate. However, I found what the car says is left in the fuel tank adds up pretty accurate to what I pumped in to fill it up to equal the fuel tank capacity.

[zamboni]

Originally Posted by crystaweizen

In an e82? Or e92..

E82.

[crystaweizen]

Originally Posted by zamboni

E82.

Is that a lot of city driving?

[zamboni]

Originally Posted by crystaweizen

Is that a lot of city driving?

Not really my daily drive from and to work was 34 miles total.

[germ]

On a 135i conv. Range estimate is extremely inaccurate (ways too optimistic) after fill-up. Becomes more accurate as tank empties. Is very accurate with tank near empty. I know because I drove it till showing 0 miles left and didn't get stranded.

[hatepotholez]

So from full to almost empty(12.956) I got only 188 miles(ridiculous). So at this point I think my gauge is correct.

[Isdaako]

I've found the gauge to be the most accurate of any vehicle I've ever owned.

[crystaweizen]

Originally Posted by hatepotholez

So from full to almost empty(12.956) I got only 188 miles(ridiculous). So at this point I think my gauge is correct.

thats strange i can make it from portland oregon to olympia washington and back on a little over half a tank and sometimes im in it pretty good. stock filter? you should run a DCI setup. less restrictive i have found.

[doublevanosrc]

Originally Posted by Isdaako

I've found the gauge to be the most accurate of any vehicle I've ever owned.

This^

However these 1 series cars have a small tank(14 gal), my E46 had 16 gallons.

[zamboni]

Originally Posted by doublevanosrc

This^

However these 1 series cars have a small tank(14 gal), my E46 had 16 gallons.

According to spec 1er only has 12.5 or 13 gals gal tank.

[doublevanosrc]

Originally Posted by zamboni

According to spec 1er only has 12.5 or 13 gals gal tank.

Nah, on page 146 in the owners manual it indicates approx 14 gallons or 53 liters. Anything less and BMW should be ashamed.

[hatepotholez]

Originally Posted by crystaweizen

thats strange i can make it from portland oregon to olympia washington and back on a little over half a tank and sometimes im in it pretty good. stock filter? you should run a DCI setup. less restrictive i have found.

I was considering that actually, maybe from AFE and also a performance exhaust.

[crystaweizen]

Originally Posted by hatepotholez

I was considering that actually, maybe from AFE and also a performance exhaust.

nice im running the injen and berk axleback and getting berk mids soon. anything that helps the engine breathe better i imagine will take a load off and increase efficiency/fuel economy

[PA135i]

I recently went 283 miles on a tank. had 1 gallon left. But that's a mixed 75 - 25 city highway mix. Still, I think thats pretty darn good.

http://www.fuelly.com/driver/pa135i/135i

[hatepotholez]

Originally Posted by crystaweizen

nice im running the injen and berk axleback and getting berk mids soon. anything that helps the engine breathe better i imagine will take a load off and increase efficiency/fuel economy

Nice. Gotta look into Berk mods.