Running on empty

[Rusty Crobar]

How far can an isf travel when the trip computer reads zero? I did about 10 miles today in heavy traffic with the gauge on empty and watched the fuel gauge drop well past the minimum level! 😮

Due to my cars, um, drinking problem I don't take any chances when it comes to refuelling but interested to know for sure how far it will go in an emergency 😀

[Big Rat]

8 minutes ago, Rusty Crobar said:

How far can an isf travel when the trip computer reads zero? I did about 10 miles today in heavy traffic with the gauge on empty and watched the fuel gauge drop well past the minimum level! 😮

Due to my cars, um, drinking problem I don't take any chances when it comes to refuelling but interested to know for sure how far it will go in an emergency 😀

@Rusty Crobar Such a bad boy can't push an isF for two reasons....

Its Auto

It weighs more than @Flytvr list of I'm not happy with Mr Lexus dealers 😂

🐀

[emjay82]

This person decided to test the reserve range but cleverly kept near to the pump... 😂 

 

[Linas.P]

This one epic... she even went to ask why the **** they don't have pumps on the "right" side...

[sorcerer]

59 minutes ago, Rusty Crobar said:

How far can an isf travel when the trip computer reads zero? I did about 10 miles today in heavy traffic with the gauge on empty and watched the fuel gauge drop well past the minimum level! 😮

Due to my cars, um, drinking problem I don't take any chances when it comes to refuelling but interested to know for sure how far it will go in an emergency 😀

As I said just yesterday in a different topic, the main reason for not running the petrol tank dry is that in petrol injection systems the fuel pump is actually inside the fuel tank and is cooled and lubricated by the fuel itself - no fuel means no cooling or lubrication for the pump, possibly leading to other (no doubt expensive) problems.

So when you say "but interested to know for sure how far it will go in an emergency" the best answer is to never find out - never let it get to that emergency situation. I would never let my cars get below 1/4 full.

 

[Linas.P]

That is interesting opinion and I quite like your reasoning as well. This actually make me to reconsider my approach as I always run well into reserve. I would say on average I put 20 miles into reserve (don't try on IS-F!) and I was doing it for 40k miles on IS250. I have't had any problem with fuel pump, but have twice ran out of fuel (luckily both times ~100 meters from petrol station). I kind of did it to fully cycle fuel in the tank, but your reasoning makes sense, thought 1/4 tanks is quite a lot, but I guess I am at least going to stop driving on reserve.

[dougie175]

Agreed much better to keep it out of the reserve, see cars all the time at work running on fumes, I don't understand it personally its like not use save money using the bottom half of the tank over using the top half? Apart from the very slight weight cost I guess. I tend to top up weekly but would be thinking of stopping at next station if I was getting to around 1/4 tank personally

[steveledzep]

Yes, top up at 1/4 or maybe just below.

[J Henderson]

I run mine 'till the light comes on (circa 20-30mls range left). There's still quite a lot of fuel left at this point. Somewhere between 5-10 litres.

[sorcerer]

34 minutes ago, J Henderson said:

I run mine 'till the light comes on (circa 20-30mls range left). There's still quite a lot of fuel left at this point. Somewhere between 5-10 litres.

I wouldn't think of it as 5-10 litres being 20-30 miles range or even as being "quite a lot" but rather 'would the petrol in the tank cover my fuel pump?' because if not then it's not being cooled or lubricated.

Ok, it may not be long after the light comes on before you put more petrol in the tank but if the fuel pump is not immersed in fuel on a regular basis (even if only for minutes at a time) then the cumulative effect may lead to problems later. Is it really worth the risk? You have to have petrol and you will put it in anyway, so why not just put it in earlier?

[J Henderson]

It's a matter of convenience, really. I normally buy V-Power and have to go out of my way to access a Shell station, so I invariably wait until I have to get fuel.

 

[Flytvr]

Once again, you've all missed @Rusty Crobar's real reason for running the tank low. Just like a formula one car, Rusty's car is fuelled for the optimum.... lap.... I mean, traffic light getaway.

@Big Rat uses a different fuelling strategy. His car will always have sufficient fuel to get to the next cake & coffee shop!

[Flytvr]

For Rusty, every trip to the shops, every daily commute is the equivalent to a Q3 qualie lap! 😀

[Rusty Crobar]

43 minutes ago, Flytvr said:

For Rusty, every trip to the shops, every daily commute is the equivalent to a Q3 qualie lap! 😀

This is true but today the missus wanted to get home early and didn't want to stop! Obviously she always gets what she wants. 

I use my car everyday so fuel stops are a tedious necessity for me but I agree with the advice, I usually fill up once I'm down to a quarter tank 😴

[MNMJ]

I almost always wait until it reaches 0 miles, or later. From extensive experimentation, 0 miles means there will be about 2 gallons left in the tank, so anything between 40 and 60 miles of driving depending on the road you are on. This works for ISFand RCF

In 7 years, my fuel pumps have never caught fire through lack of cooling.

[Flytvr]

If you bought your car from a garage, you can guarantee it will have been run on empty quite a few times. 

[Big Rat]

8 hours ago, Flytvr said:

Once again, you've all missed @Rusty Crobar's real reason for running the tank low. Just like a formula one car, Rusty's car is fuelled for the optimum.... lap.... I mean, traffic light getaway.

@Big Rat uses a different fuelling strategy. His car will always have sufficient fuel to get to the next cake & coffee shop!

@Flytvr Ah yes a man who knows me well and that refuelling comes in many many guises 😁

🐀

[Big Rat]

21 minutes ago, Flytvr said:

If you bought your car from a garage, you can guarantee it will have been run on empty quite a few times. 

@Flytvr No ain't that the absolute truth 🙄

🐀

[emjay82]

1 hour ago, Flytvr said:

If you bought your car from a garage, you can guarantee it will have been run on empty quite a few times. 

You're right there @Flytvr. Another happy customer on his way home from the garage here..... 

 

[Linas.P]

@emjay82 - that is because of USA and because of NSO is nearby... 

10 hours ago, MNMJ said:

I almost always wait until it reaches 0 miles, or later. From extensive experimentation, 0 miles means there will be about 2 gallons left in the tank, so anything between 40 and 60 miles of driving depending on the road you are on. This works for ISFand RCF

In 7 years, my fuel pumps have never caught fire through lack of cooling.

Similar to what I do. It is quite interesting to know that you can make 40-60 miles in RC-F and IS-F. I would say IS250 car do about 30-50, which means that Lexus scaled reserve fuel accordingly. I always though IS-F had same tank as IS250 and as such less reserve, but I must be wrong then.

For me refueling late is as well kind of convenience thing, visiting station less often. But again is has 65L tank and the most I have ever put in it was 64.3L and 63.8L (once I ran out of fuel) and most of the time it is ~59-61L. Refueling at 0 miles range would be ~55L, which I believe I am going to start doing now because of @sorcerer reasoning... Refueling at 1/4 would mean I will visit petrol station 30% more and that is why I am not fancy doing it.

[dougie175]

I just make it part of my weekly routine 90% of the time it is Friday afternoon on my way home from work whatever is required I just fill her up, after a week of work and a bit of driving of an evening its usually 2/3 or a tank or so.

[JonP]

I once ran out of fuel many years ago, in a very inconvenient part of the world in an old car with, as it turned out, dodgy electrics. I guess I was scarred for life by the experience, because I have made sure I always fill up early. The sight of that little yellow petrol pump glowing at me makes me come over all strange.....