Fuel........always keep some spare or let it run down?

[Harji]

A few years ago, while contracting out in Newbury, a few of us who used to drive from London decided to do a efficient fuel run type of competition, most miles per tank, mpg, etc etc. Nothing hard and fast , just mentioning what we achieved, my first year I used a Subaru Legacy 2.5 petrol, I was up against a Honda civic and a Merc C class.
The next year I decided to go full diesal with a BMW 320d, now if I remember it was a 61 litre tank, on one fill up I actually filled 60.5 litres of fuel. I was the top dog.

[King Herald]

Burgerbob said:

. As a lad in the cadet force I was told that they refuel aeroplanes after use as it limits the build up of condensation in the tank. Hence, as the van sits unused for weeks at a time I apply the same logic and leave it fuelled. No idea if there is any truth in this or not!?

I pointed that out on the bike forum, discussion about parking a bike up for months, and was told ‘get real’ and some other choice comments, by a couple of pimply know it all teenagers, no doubt.

I assumed it was fairly common knowledge amongst motorists with a little brain.

[national]

I like to run it down as far as I dare. I've once filled up with more litres of fuel than the fuel tank on my car, I think I did pretty well that time.

[SonicShadow]

TooMany2cvs said:

Is it only mapped for 98? If so, then it'll just pink on 95.

Or does it have a knock sensor, and a fall-back 95 map?

Mine has to be run on 98+, the moment you hit boost on 95 the knock sensor will trigger and timing gets pulled so hard it's basically limp mode.

[TooMany2cvs]

SonicShadow said:

TooMany2cvs said:

Is it only mapped for 98? If so, then it'll just pink on 95.

Or does it have a knock sensor, and a fall-back 95 map?

Mine has to be run on 98+, the moment you hit boost on 95 the knock sensor will trigger and timing gets pulled so hard it's basically limp mode.

Shame they couldn't be arsed to simply manage the boost, like people have been doing perfectly successfully since the 80s.

[SonicShadow]

TooMany2cvs said:

Shame they couldn't be arsed to simply manage the boost, like people have been doing perfectly successfully since the 80s.

No need to for it's original market as 98+ is universally available.

[ashleyman]

I used to run mine down all the way to 0, got caught once and ended up doing 28 miles on 0. When I eventually filled up I put in 59L in a 55L tank!

I don't leave it like that now, opting to fill up when I've got about 15 miles left on Range. I'll always fill up before a long journey though because I don't like stopping and paying inflated motorway prices.

[AC43]

I usually let it run down at home but nearly go caught out in France when I did this. I arrived very late for an overnight stop in the middle of nowhere. Was running low but just wanted to get in, get fed & watered and get my head down.

The next morning I set off and my host insisted on showing me a cross country route that shaved a bit of distance off. The moment he peeled of to return home the fun started. The reserve fuel light came on.

On the motorway this would have been no great shakes but I wasn't on the motorway. I was in the arse end of beyond in a fully loaded 5.0 V8 E Class estate (ie family of four, a boot full of clobber and a roofbox, similarly rammed).

And then it turns out it was one of those random days off in France where everything was shut including, of course, all rural petrol stations.

The range gradually counted down from 25 to 15 to 10 to 5 to 0 miles and there it was! A filling station. That turned out to be shut and whose self service pumps were bust.

Got back on the road and managed another 15 or so miles on zero trying to hypermile my gas guzzler and a second one appeared. Also closed but with card pumps that actually worked.

Managed to get 79 point something into the 80 L tank.

Next time I went there I filled up on the way. And made sure I left on the sodding motorway....