I apologize if this has already been answered but I did some looking and couldn't find any info on this. I recently purchased a 2013 Prius Plugin and have driven 1,500 or so miles over the past few months. Twice now, I've let my gas gauge go all the way down to where it starts blinking and the estimated miles left in the tank say about 5 miles. My tracked mileage for the tank is about 400 miles. When I go to fill it up, I put about 7.5-8 gallons of gas in to fill the tank. From my understanding, my prius has a gas tank of 10.1 gallons. I haven't wanted to test this out too much and be stranded on the road, but it looks like the estimation for miles left in the tank and my gas gauge are about 100 or so miles off. I know all cars have some sort of fuel reserve, but 2 gallons seems a bit much for a car, especially a Prius. Has anyone else experienced this? Is there an issue with my sensor? Any information about this would be helpful.
Your DTE (distance to empty) could be reading zero miles left and you still can go another 50 miles. The car's ECU does a conservative estimate based on your driving style. It also doesn't want you to run out of gas climbing a mountain up to Denver - that's why you have such a wide variance. There's no substitute for the human brain..... I once did an addition 30 miles past my DTE on my gas sucking GMC @ 17 mpg. I was on fumes when I got to a pumps, still had a half gallon in the tank.
Thank you. I figured that was the case but 2.5 gallons left when the DTE is zero just surprised me. I figured it would be more like .5-1 gallons left before it said zero. Glad to hear there’s nothing. Wrong with my sensors though.
You shouldn’t let it get that low. You risk overheating the fuel pump. You should start looking to fill up about half a tank. fill the tank, reset one of the trip meters, fill up around half a tank. Divide the mile by gallons to get your actual fuel mileage...
it is two gallon reserve. should be in your manual. mine always takes 8 gallons from the blinking bar wheni use the same pump. toyota is a very conservative company.
11.9 gallons is the tank capacity, but the manual is only another mans opinion. When I fill up DTE at zero, I actually have 2.5 gallons left when refilling. You can thank gen 2 owners’ for that excessive headspace.
My experience with my Gen 3 was that mileage was accurate as long as you drove normally, and without a lot of accessory drain. It tries to make a guess based on what it reads as fuel consumption. I ran completely out of fuel twice. Once, I got 180 kms after the light came on. At that point, it would only run on electric power, and was limited to about 30 kph. The other time, I pushed it until there wasn't even enough battery left to roll up the windows while I walked for gas. I was trying to make it to a gas station, but it stopped about a hundred metres short. Startup was easy once I had gas in the tank. The electric fuel pump primes the system and it starts up normally.
since you drained the battery also, how did you get the engine started? What kind of gas did you use to charge up the hybrid battery so it would turn the engine over? I WANT THAT GAS!!!
When I drove my gen 2 until it ran out of gas , and kept going until the dash lit up and the car rolled to a stop, it started right up with 3 gallons of gas. The software must protect the battery from getting too low
Yep, my understanding is - If you continuously try restarting the car - it'll eventually lock you out. Putting at least 3 gallons in and disconnection the battery for 15 minutes will be the only way to restart it from an ECU lock-out.
As I recall, it had enough residual charge to start up the car. If not, I suppose I gave it a boost. I don't think the system would ever let the hybrid battery get so low that it wouldn't turn over the gas engine. The lack of power I experienced was from the 12V battery going dead, because the system refused to drain any more from the hybrid battery.
If your 12V battery went dead, you would definitely need to jump start, it to close the traction battery relays. If you activated the ECU lock-out, you would need to meet minimum ECU specifications (ie. move the gas tank needle - usually about 3 gallons), then clear/reset the ECU or disconnect the 12V battery for 15 minutes to make it forget the lock-out condition.
