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TJPark01
12-31-2010, 12:13 PM
I got a low fuel warning on my 535i last night. Although I usually fill up the car when the needle gets a little past 1/2, I have been busy with holiday things.
I continued driving for another 30 minutes or so in heavy traffic. I got gas on my way home filled it with 16 gallons of fuel. Which means I had 2.5 gallons left in the tank. The computer told me I had 40 miles of range left, which seems about right. Although I appreciate the warning, I found it to be rather annoying that the car kept repeatedly reminding me of my fuel situation. I think 1 warning would have been enough.

raleedy
12-31-2010, 01:37 PM
My '57 VW had no gas gauge. There was a valve on the firewall, in the middle. The normal position was vertical. You drove until the engine coughed, then you pushed the lever a quarter turn to the right (it's now horizontal) and went off to get refueled. With a little practice, the lever could be moved with the right foot from the driver's seat, and hardly a beat was missed. That was a "one warning" system. You can imagine that, from time to time, one would forget that the warning had already been received.

markl53
12-31-2010, 03:32 PM
Although I appreciate the warning, I found it to be rather annoying that the car kept repeatedly reminding me of my fuel situation. I think 1 warning would have been enough.

Interesting. I rarely let the fuel go very low, but in my previous 335i, I think I remember that the alert only pops up once per enging start session. You get the chime and light -- I don't remember it continuing to chime. Similar to the 37 degree warning alert, you only get that one time until you shutdown and restart. Was it every few minutes? What was the cycle time between alerts?

laser
12-31-2010, 03:38 PM
Haven't run it down on the F10 but the E60 535i was persistent to the point where, if not heeded, the warning came back on and visually obliterated portions of the navigation and other car info on the center display as well as the navi screen .......

TJPark01
12-31-2010, 06:35 PM
Interesting. I rarely let the fuel go very low, but in my previous 335i, I think I remember that the alert only pops up once per enging start session. You get the chime and light -- I don't remember it continuing to chime. Similar to the 37 degree warning alert, you only get that one time until you shutdown and restart. Was it every few minutes? What was the cycle time between alerts?

Hard to tell as I made a few stops.

beashonda
12-31-2010, 07:01 PM
I got a low fuel warning on my 535i last night. Although I usually fill up the car when the needle gets a little past 1/2, I have been busy with holiday things.
I continued driving for another 30 minutes or so in heavy traffic. I got gas on my way home filled it with 16 gallons of fuel. Which means I had 2.5 gallons left in the tank. The computer told me I had 40 miles of range left, which seems about right. Although I appreciate the warning, I found it to be rather annoying that the car kept repeatedly reminding me of my fuel situation. I think 1 warning would have been enough.

That is the reserve of 2.5. Your car is new so there's less sludge or dirt or sentiment at the bottom of your fuel tank at this point. However, the manual says to refill I believe at ~50-60 miles to go. Remember depending on your driving habits, that may not be 100% accurate and could drop to lower than that.

Imagine how annoying it would be to run out of gas...............:yikes:

TJPark01
01-01-2011, 11:28 AM
That is the reserve of 2.5. Your car is new so there's less sludge or dirt or sentiment at the bottom of your fuel tank at this point. However, the manual says to refill I believe at ~50-60 miles to go. Remember depending on your driving habits, that may not be 100% accurate and could drop to lower than that.

Imagine how annoying it would be to run out of gas...............:yikes:

It would be horrible, and I imagine it's a safety feature. I guess one has to accept that cars are going to continue to evolve into more "nanny tech". I guess it's the price to pay for less impact on humans.

Financeman
01-01-2011, 05:05 PM
Perhaps the overly aggressive low fuel warning might relate to fuel pump life...in some vehicles low fuel can cause the fuel pump to operate a little warmer than normal, reducing pump life. Just a thought.

Rafa
01-01-2011, 06:48 PM
Perhaps the overly aggressive low fuel warning might relate to fuel pump life...in some vehicles low fuel can cause the fuel pump to operate a little warmer than normal, reducing pump life. Just a thought.

Good observation.

In general, I think we should look for a gas station at 1/4 full. That would minimize the soiling of the fuel filter, and keep the pump temperature more in the green zone as you mentioned.

AzNMpower32
01-01-2011, 09:29 PM
The newer BMWs don't have a dedicated low-fuel light that permanently stays on like in the older BMWs (E46, E83, etc...). Hence, the repeated Check Control message is the way of constantly annoying, haggling the driver to full up.

gtmaster303
10-18-2016, 07:37 AM
Reviving this thread because I'm currently hypermiling my 2012 528i xdrive. Covered 500 miles, trip computer says I've averaged 33.4mpg. Fuel light came on at 480 miles
Says I will run out in 40 miles. Want to fill up at Sam's club which is 54 miles away on my commute home. The range doesn't drop very fast on the highway. I can cover 20 miles and only lose 10. But locally it drops at a normal rate. Commute home tonight is almost all highway

Will I make it? Not intending to run out of gas, but at the same time I want to push it

ezaircon4jc
10-18-2016, 04:32 PM
Reviving this thread because I'm currently hypermiling my 2012 528i xdrive. Covered 500 miles, trip computer says I've averaged 33.4mpg. Fuel light came on at 480 miles
Says I will run out in 40 miles. Want to fill up at Sam's club which is 54 miles away on my commute home. The range doesn't drop very fast on the highway. I can cover 20 miles and only lose 10. But locally it drops at a normal rate. Commute home tonight is almost all highway

Will I make it? Not intending to run out of gas, but at the same time I want to push it

Why??? If the fuel pump is in the tank (as I believe all injected engines are that I'm aware...) the fuel cools the pump. Electric motors don't like heat and the motor needs the fuel to keep it from heat-related failure. I've been told my more than one tech/mechanic that it's not a good idea to regularly get below 1/4 tank because the pump needs the fuel for cooling. I've followed this principle and regularly keep my cars for 150K+ miles and have never had a fuel pump fail, FWIW.

gtmaster303
10-18-2016, 04:51 PM
Why??? If the fuel pump is in the tank (as I believe all injected engines are that I'm aware...) the fuel cools the pump. Electric motors don't like heat and the motor needs the fuel to keep it from heat-related failure. I've been told my more than one tech/mechanic that it's not a good idea to regularly get below 1/4 tank because the pump needs the fuel for cooling. I've followed this principle and regularly keep my cars for 150K+ miles and have never had a fuel pump fail, FWIW.
Not a regular thing. Just want to explore my car's limits. I've never had a fuel pump fail on me. Had dozens of cars, all that have gone more than 100k

ezaircon4jc
10-18-2016, 04:57 PM
Not a regular thing. Just want to explore my car's limits. I've never had a fuel pump fail on me. Had dozens of cars, all that have gone more than 100k

I tried it once with my 535i.... I chickened out with 25 DTE... From my admittedly limited BMW experience (21ish months and 32Kish miles) the fuel gauge appears to be pretty accurate. With the 25 DTE reading I had about a gallon and a half left.

gtmaster303
10-18-2016, 08:45 PM
So here are my results:
I made it!

Car's trip computer said I averaged 33.9MPG

Filled up 17.5 gallons, covered 562 miles. Based on my calculations, I averaged 32MPG. Not what the car registered, but still super stoked! A good mix of local and highway driving. (estimated 70% highway, 30% local)

On my trip from work to the gas station tonight (54 miles total - 30 miles interstate, 24 miles highway with traffic lights) I averaged 39.4MPG!!!!!

Car read 0 miles on the tank and I was still able to drive 6-7 miles to get to the station.

Some notes:
-Car will have a constant fuel warning once you hit 30 miles of range left
-Eco pro mode tells you how many miles you've added in blue on the dash display. At the highest point it was 21 miles. That number quickly dropped to zero, as the range went down from 30 to 0 (not sure why)
-You can safely assume there's at least 1 gallon of gasoline left in the car )possibly more) even after range says 0 miles left. I need to better understand how gas pumps work, but they don't brim the tank, I think. Also the F10 has a rated fuel capacity of 18.5 gallons, but I'm not sure if that assumes the car has been brimmed with fuel, or just a standard pump until the first click where it turns off.
-If you fully brim the tank (ie, keep clicking the gas pump until car is completely full) you can go 600+ miles on a tank if you're careful enough. Again, not sure if when you keep clicking to add more fuel if you're exceeding the 18.5 gallon capacity, or not. But 600+ is definitely possible
-I did drive fast. During this tank, highway speeds were usually around 70-80. There were at least a handful of points where I hit 90mph and at least 2 occasions where I hit 100mph. Importance needs to be placed on aggressive starts and getting up to speed. Done gradually, in pulses, working with downhill roads, and not charging up hills, you can still drive fast and also get great fuel economy.

I know this is not what the car is made for, but at least I know the limits and what this car can achieve. Properly amazed and very happy with the results.