Right, heres the dillema,

This morning on the way to work, my fuel light came on, now I would really like to not put any fuel in until we go shopping tonight at tesco's (cheaper, means I don't have to go out of my way as there is no fuel stations on my way home), but being a diesel and the subsiquent issues if it does run out of fuel I am a bit concerned about it, its at least 20miles to tesco's.

The thing is, my OBC (on board computer) is saying I have at least 60 miles left in the tank, but I have no idea how accurate these are..........

Help me out

They're always way too pessimistic even when they reckon the tanks empty you probably have a good 30 miles left.

Don't cars always have a safe reserve that let you go at least the distance of 1 to 2 more gallons once the light comes on?

When I was young, my father would drive me to school, and when we left the light would be on, and he'd go drop me off +10 miles, then head to work +40 miles. He'd sometimes come back and the light would still be on lol! You can go something like 30 to 60 miles I'd imagine. BUT I've learned it is never good to drain it out with the light on... especially for a fuel injected car is what I've been told before.

So I usually refuel even before the light comes on, I never try and get the fullest out of my tank, unless I am on long drives travelling.

So you have 20 miles to go and it says 60 on your computer? I'd go for it, the margin is so great, and what I've seen, these OBCs are very pessimistic.

I know it's a worry with a diesel as you have to bleed the whole fuel system if you run it dry, but I'd be tempted to leave it if you've got 40 miles to do today before you arrive at Tesco.

My fuel light comes on at 1/8th of a tank on the gauge, and that's a good 60 miles for me. Go easy on the loud pedal and fill up at Tescos.

Or, check out www.petrolprices.com and find what's cheapest near you.

Yeah, I am gonna go for it.....

As for prices, around my neck of the woods I am very limited, I have a choice to go to Esso and pay through the nose for it, or tesco's and get it cheap(er)

Don't know about diesel, but I get more miles per pound using Optimax (V-Power if I must) than using cheap supermarket fuel, as well as having other benefits too. Although Tesco99 is supposed to be good stuff, as is BP Ultimate. But there's a Shell garage just up the road, so I use that.

Quote from tristancliffe :

Don't know about diesel, but I get more miles per pound using Optimax (V-Power if I must) than using cheap supermarket fuel, as well as having other benefits too. Although Tesco99 is supposed to be good stuff, as is BP Ultimate. But there's a Shell garage just up the road, so I use that.

I read an article (printed, so no link, sorry) comparing those three fuels. Apparently the Tesco stuff was pretty awful compared to the other two, with V-Power/Optimax being the best. It wasn't really a comparison with fuel consumption in mind, they were using a test engine to compare the amount of power at a fixed igntion point, then they tested to see how far they could advance the timing without knocking.

Fuel's fuel IMO, I really don't think it would matter what I put in a 90bhp 2.0lt Diesel LOL.

Might make a minute difference in a tuned turbo car, but not in my little thing.

http://www.thorneymotorsport.c ... g/Fuel_Test_Results.shtml

Thats an interesting article with a test done on 4 different fuels (Total 95, BP Ultimate 97, Shell optimax, Tesco99) and tesco is pretty much a clear winner, although they were testing it on a MR2 and a tuned M3, but they say theres more than a 10% difference.

Interesting, but the difference on the MR2 is 1-2bhp at best

Did Clarkson not drive a diesel and a petrol polo around some motorway in England to see when it would run out of fuel?
He's always running cars till dry and seems to me they pretty much are spot on, within the nearest kilometer in some cases on TG

my Toyota OBC is veeeery inaccurate, on a full tank it reports around 280-300 miles of petrol, 350 miles later there's 1 flashing bar left on the petrol gauge.

Also I ran it down to 0 miles, but the dash reported there was still 1-2 bars left (couldn't decide when i was going up/down hills on flat it stayed at 2 bars). 30 miles later it eventually dropped down to the 1 flashing bar, so 10 miles after that I filled it up.

Quote from CSU1 :

Did Clarkson not drive a diesel and a petrol polo around some motorway in England to see when it would run out of fuel?
He's always running cars till dry and seems to me they pretty much are spot on, within the nearest kilometer in some cases on TG

I actually saw that episode last week as a rerun. He drove around some M something road, not to dry it up, but to see how much he had to fill it compared to the petrol version if I recall correctly....and spend the saved money on a golden cock in the shop

Quote from Blackout :

I actually saw that episode last week as a rerun. He drove around some M something road, not to dry it up, but to see how much he had to fill it compared to the petrol version if I recall correctly....and spend the saved money on a golden cock in the shop

Oh yeah, I remember now, and his DVD was thrown in the bargain bucket in the shop lmao, he wasn't too happy with that

He is always driving them dry though, was there one where he drove from north to south of England and the OBC still didn't lie depends on the make/model of the car at the end of the day I suppose....

Quote from CSU1 :

Oh yeah, I remember now, and his DVD was thrown in the bargain bucket in the shop lmao, he wasn't too happy with that

He is always driving them dry though, was there one where he drove from north to south of England and the OBC still didn't lie

yeah, he drove from london to somewhere in scotland and back again on 1 tank of fuel.

Audi A8 diesel I believe.

I suppose if you car was a petrol you would have no worries in filling up a gallon can and waiting till it konks out to see how accurate the OBC is, but as we all know if you do that with your car you will spend twenty minutes at the side of the road pumping and shouting prophanities at your car

Do modern diesel engines still get air locked and require you to manually get the juice back up to the engine?

I never have much faith in the OBC's reading, in the C4 I used to drive, once the fuel light came on at ~40 miles with 2 flashing bars, you could do those 40, then have no flashing bars, then do another 20 before its time to look for a fuel station. Then you put a tenner in, and apparently you'll only get 50 miles out of that.

A friends Pug 406 2.0 diesil was similar, once the fuel light came on, he could drive to work and half way back before it started complaining (~80 miles).

Quote from CSU1 :

Do modern diesel engines still get air locked and require you to manually get the juice back up to the engine?

I believe so, although I have very limited experience with diesels. The reason is the fuel pump in a diesel is made with very tight tolerences, and requires the fuel (oil) to lubricate it. Attempting to make it pump dry (or with petrol in it) will quickly knacker it.

Of course, the owners manual should inform you whether it's required on your particular car.

Yeah, its a pain in the arse, I have heard that pug HDi's (which I have) can be particularly hard to get going again, due to the high (2000psi would you believe) pressure pump, they can also fail and costs about £3000 to fix.....eeepppp

Quote from tristancliffe :

I believe so, although I have very limited experience with diesels. The reason is the fuel pump in a diesel is made with very tight tolerences, and requires the fuel (oil) to lubricate it. Attempting to make it pump dry (or with petrol in it) will quickly knacker it.

Of course, the owners manual should inform you whether it's required on your particular car.

yes, as with any fluid pump running it dry for too long will no doubt end its life.
But I believe that on most diesel engine fuel filters(that I worked on) there is a manual pump located on top of the filter, and if your lucky you could pump the fuel back into the engine without having to release the air lock...if your lucky.

We'll see in about 2 hours time LOL

Quote from danowat :

We'll see in about 2 hours time LOL

Dont do it dan, it aint worth it

Edit:

I bet you wind up like this pair trying to get it going again lmao!!!

HES OFF, news just in from msn that Danowat has left his work in the light up car! Can he make it home? Put your bets on it here!

If we never hear from him again, I will assume that he ran out of fuel and was ravaged by a pack of wolves