Driving w/Gas Light: How Long?

[SEBPOP]

Okay, so I used to have a 98 Camry 4 cyl. and I would easily drive 45 miles with the gas light on (I think it had a 2 gal reserve). Then I had a 99 Camry, same deal. Now I have an 09 hybrid and the stupid trip computer tells me I have 0 miles left approximately 2 miles after the light turns on. Of course this freaks me out and I gas up, and I'm lucky to get 15.4 gallons into the 17.2 gallon tank.

If it wasn't for that damn computer telling me I'm going to run out THIS INSTANT I wouldn't be scared. How long/far have others driven with the gas light on and the computer telling you to fill up b/c you've got no more miles left. I just bought this car and I'm getting approx 400 miles to the tank (but to a 15.2-15.4 gal tank, not the 17.2 per my calculation), and I want to see how many miles I can really get out of it, without running out of course.

I assume the engineers did this because its bad to run the tank extremely low due to picking up trash at the bottom, but let me hear some feedback.

Also, anyone getting much better gas milage running 93 octane. I just got out of an M3 and into the TCH to get away from the 93, but if it helps enough to warrant the extra price, why not.

[darrelr]

When my gas light comes on, I have used roughly 13.4 gallons of gas. I panicked and filled up after driving 5 miles. That is how I found out. Now I usually reset the trip B meter and drive another 100 miles before I fill up.

[SEBPOP]

Wow, I'll remember that 100 miles is a lot, thanks for the info

[LCromwell]

Originally Posted by darrelr

When my gas light comes on, I have used roughly 13.4 gallons of gas. I panicked and filled up after driving 5 miles. That is how I found out. Now I usually reset the trip B meter and drive another 100 miles before I fill up.

Most gas lights allow for a reserve of around 5 gallons.

[darrelr]

On my previous vehicles (2003 Tundra, 2005 4-runner) the fuel light would come on, and there was only 1-2 gallons left in the tank. That is why I was surprised on my first trip with this vehicle.

[cdn_tch]

I don't see the point of running the car down to fumes in the tank. You will burn the same amount of gas with either a full tank or empty one so why risk running out or having to have to stop for gas when you are in a hurry.

For me, anytime it hits a quarter tank is time to fill up at my convenience, usually within the next 4-6 days.

[razol]

My TCH flips on the light far earlier than any car I have every driven before. Like you, I was paranoid and filled up straight away. A couple of time in this routine and I realized that I was only putting in 13 gallons per fill-up. Now when my cruising range hits zero I either mentally note the mileage, or reset the trip B setting. I drive about 100 more miles and still generally only fill up under 16 gallons.

Once I was in a rural area and did not find a petrol station, I drove 150 miles on empty and the I still did not fully deplete the tank.

Add the fuel light to the list of other naggy features of this car that I try to ignore. It is a great car mechanically, but I will celebrate when I am in the position to get rid of it.

[cdn_tch]

I don't get it. It is a gas guage which is overly optimistic.

Why would you care if you put in 13 gals or 15 gals? You will put in the gas eventually!

I remember a friend in the 70's who had a Pinto, the first half tank was 300+ miles, the second half was 25. It only took once, and she filled it up whenever it hit half a tank.

[Pipemajor]

You really don't want to run a hybrid vehicle dry. The Toyota manual specifically says NOT to do this.

As another poster said, you'll consume the same amount of gas filling it up 12 gallons at a time or 16 gallons at a time.

When I get down to ¼ tank, it's time to fill up.

[AmanO]

Some of us do not like going to a gas station. So we do it as little as possible. Are there reasons to NOT wait? Other than the threat of running out of gas, if you don't run it down to actual fumes, whats the issue with waiting?

I am not sure of the math, but it seems like filling up at 3/4 tank as opposed to 90/100th tank would add 12-36 unnecessary trips to Exxon each year.

The only other thing I could see is filling up when gas is cheaper. i.e. Thursdays around here. But then you can still get burned (pun intended)

[cdn_tch]

Originally Posted by AmanO

... I am not sure of the math, but it seems like filling up at 3/4 tank as opposed to 90/100th tank would add 12-36 unnecessary trips to Exxon each year...

At 20,000 per year at 35 mpg at 15 gal fills (about when the light comes on) is about 38 fills/year; at 17 gal fills it goes down to 33 fills/year.

I still dont see why the fuss. If the car got 20mpg, that 2 gal reserve would be gone in a day. Since the TCH can get over 40 mpg it lasts a lot longer.

Also, please realize that the miles to empty number will never go up, so when you are low and have a cold start or drive such that your instantaneous mileage is low, the computer recalculates miles to empty based on the current consumption, possibly getting to 0 (with some reserve still planned for) far earlier than a longer average would give.

[AmanO]

Well, a quarter tank would be more like 4 gallons. So your figure of 5 extra could be more like 10. Still not that many, but why do it at 3/4 when you know you can wait till 9/10 and still be fine? That is the question. You use the word fuss, but you were the one to start asking why.

Just like people who say driving fast on the E-Way does not help. It can.

[razol]

For me it is a matter of practicality. I have to drive 4 towns over to get fuel. If I fill up when the light comes on at one quarter tank, I would be making a lot of wasteful trips into town.

[honest_abe]

There are some definite reasons to wait.

When traveling, some neighboring states have 20 cent a gallon cheaper gas.

Some towns/areas have cheaper gas when driving locally.

[SEBPOP]

I had no idea people would be so adamant about not running the tank down low. I have to be honest, I've always ran my cars down after the light turned on, the main reason, and the reason why I want to now, is to determine how many miles I got out of that particular tank. I just bought this camry and there is no way to know how many miles I'm getting without really doing a test like this at least a couple of times. Furthermore, I tank up at one of these "buy in bulk" stores that happens to have the cheapest gas around, so to me, it's good to know how long I can go (aka, whether I should stop today after work, or can I go one more).

I agree, you shouldn't let the pump pick up trash at the bottom of your tank, but I don't like stopping if I don't have to either and I'm in a hurry.