At my last fill up, I mistakenly grabbed the 93 octane nozzle and dumped 12.5 gallons in my tank. At first, I tried to pump the fuel out when I got home, but could not get a hose to the fuel level. Additives such as ethanol are use to increase octane which screw up the oxygen sensors in the FEH.. This has cause me loses of as much as 15 % in FE. My only alternative was to take the hit and burn the tank off through the engine.

Today, I started my commute with 40 miles past 0 MILES TO EMPTY and put a can of regular gas in the back to prepare to run out of gas.

From those posting on running out of gas awhile back, I expected the engine to shut down and a warning light to come on telling me to come to a safe stop. This did not happen, the LOW FUEL message did not change. Also, we were told that you were restricted to something like 22mph in EV to get to a station. This was not true today.

Here is what happen when I ran out of fuel:

I got on I-95 and was accelerating, but traffic started to slow from 50mph. I went EV at 40mph with only 20% SoC in the battery. Traffic started to pick back up from 30mph, so I hit the gas to go ICE ON and accelerate with traffic. The ICE would not come on, but I accelerated the fastest I have ever done before to 41mph. At first, I thought the ICE was running and the tach stopped working. I was afraid to exceed 41mph in EV, so I back off to 40mph and drove to the nearest exit (about 3/4 mile) and an additional .2 miles to a parking lot. I turned the key off, and tried to restart. Nothing, the FEH acted like I had it in “D” or something. Tried it a few more times, and it started, but idled like it was running out of gas so I turned the key off right away.

I was amazed that the FEH continued down I-95 at 41 mph on a drained battery. This means I dropped the low side of the battery to a level I’ve never been to. What happen after I added gas to the tank and started the FEH was very interesting. to say the least. As I started to back out of my space, an older person was having a hard time getting his car out of his space, so I had to sit there for a few minutes. All of a sudden, the ICE started to tach up like it does with over regen while I was waiting (stopped) for this man to get out of my way. Strange, but all I could think of, was too much charge from the small generator was overheating the battery which may have been at it’s limit from the 41mph EV run. As I got going, the battery level did not show on the Nav energy screen yet, so I tried a fake shift to boost it up. No regen was possible for two miles and the battery level started showing about 25% SoC.. The battery continued to be very sensitive for about 5 miles.

GaryG

 

Gary,
I enjoyed reading you post and I will have to search for the other posts about runniing out of gas. My mother-in-law drives a Prius. She told me when her Prius runs out of gas, it lights up like a christmas tree. She has had her Prius for about 18 months and accidentally ran it out of gas twice.
I, myself has never ran any vehicle out of gas. I knew with a convensional vehicle, you'd just put gas in the tank and then try to start it. With the FEH, I am even more parinoid at the thought of running out of gas. Although I try to run the DTE as close to 0 as I comfortably can. The closest I have ever gotten was 2 miles to empty and that was on my old Durango. With the FEH, the closest I have gotten was 7 miles to empty. However; when I filled the tank inthe FEH, the most gas I was able to pump was 13 gal (we all know the fuel system holds 15 gal.)
This is also why I found your post intriguing

 

Hide these posts if you ever have battery related warranty work.

 

Hi Shannon

No need to hide the fact of how the FEH performs when put to the task. If the FEH sits for a month or two, you can expect the HV battery may go completely dead which did not happen to me. Now if I had not done the right thing and exited the freeway and stopped ASAP, Ford would have a beef to pick. It was good that I knew and didn't exceed the electric motor speed limits or continue to drive the FEH till something got damaged. There is no question that if my battery can withstand the amount of EV driving I do till the warranty runs out, your batteries should all last far longer.

BTW, based on my mileage from 0 Miles To Empty, I had about 1.28 gallons left to burn before the engine ran out of gas.

Rihavo, thanks and glad you enjoyed the post. Based on your mileage, you can now see how far past 0 MTE is possible. This seems to be about the same amount of gas in other Fords I've owned, based on how far I've (my wife recently) gone past 0 MTE in them. Thank God for cell phones!

GaryG

 

In case I am missing something.......why would someone want to cut it so close to running out of fuel? Given that the tank was full of "expensive" gas, why not simply refuel when half full, with the subsequent dillution of the 93 octane fuel each time you refuel? Why go thorugh the aggravation of having to carry a gas can within the car, with its attendant risks of fire in the event of an accident, when you knew you might need it? Guess I am a little too logical (in my mind) and would like to better understand.

Yes, I never let the car go below 1/4 tank, and have been known to top off when at 1/2 if I see a station with a "good" price.

Thanks.

 

Interesting info - I am rather surprised you did not see any warning lights or messages about running out of gas. I almost always refuel before the Miles to Empty flips to saying Low Fuel.

Keep in mind the in the fuel pumps are cooled by the gas flowing through them. I don't know if Ford programed the FEH to shut down the fuel pumps when you run out of gas. I know my F150 does not - lost one of the in tank pumps from running out of fuel once too often. Having two tanks let me be lazy about switching tanks when one was low.

 

Fantastic info Gary.

Base on this experience can you estimate roughly how many miles you can travel using the ICE, from the time the 'Low Fuel' came up to the point your tank was empty? I know you mentioned something about 1.2 gal. I'm just curious as to how long you can push the engine before you find a gas station while cruising on the highway? Usually, 25 miles is the norm, is it not? (I know, I know, there are many factors such as speed, road conditons, etc... that influence miles, but please take a guess )

 

GMan:
Did you come to any conclusions about the total number of gallons your tank holds?

MM

 

"Low Fuel" comes up 4 times: at 50MTE, 25MTE, 10MTE, and 0MTE (and whenever you start it up when you're below 50MTE).

I've found that 0MTE hits at around 13.5 gallons burned. Theoretically that would leave 1.5 gallons, which in my experience seems about right. I've run it out of gas twice and it was at around 1 - 1.5 gallons after 0MTE.

 

Gary, I'm not sayin' you are abusing your hybrid it was more a tongue-in-cheek "Careful what you wish for" type post. I personally don't like running down to Low Fuel/0 MTE in any vehicle due to the nature of the type of vehicle use I do. I've had to bring gasoline to my mother on three occasions because she does run herself low but then forgets and starts on multi-stage errands (as I do) and *poof* no gasoline {this is in her '97 Camaro, not a hybrid, but anyway.) And I want my vehicle to always be able to go ICE on if it feels the need to do so (for power, battery cooling, etc.)

Sounds like the FEH behaved perfectly safely for the given situation and you gathered useful data in the process. I just wouldn't replicate it on my $32k vehicle.