OP
OP
that means you paid pertol station prices for the 5l can too
you wiped out time and MPG savings
Time to go hang myself from a tree
Technical 2 things off my to do list .....
- Thread starter 306maxi
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Technical 2 things off my to do list .....
Time to go hang myself from a tree
Well I'm not getting a diesel 500 that's for sure. I quite fancy a Bravo as a 3rd car, I'd probably go for a diesel or a t-jet
T Jet Sport 150
https://www.fiatforum.com/members-motors/250094-bravo-tjet150-sport-crossover-black.html
Yea then swap engines around, T-jet in the 500, 1.2 in the Bravo!
Did you do the calculations then? After putting 5 litres in, then using a bit on your way there etc?
Did you do the calculations then? After putting 5 litres in, then using a bit on your way there etc?
OP
OP
Yea then swap engines around, T-jet in the 500, 1.2 in the Bravo!
Did you do the calculations then? After putting 5 litres in, then using a bit on your way there etc?
It was a couple of hundred metres to the station all downhill so the amount of fuel used would have been negligable. So perhaps it might have used a 100ml or something small but it's not an amount that's worth thinking about.
I see, was just trying to work it out myself, quite hard to get your head around how many litres used when you use MPG, especially for such a small amount.
OP
OP
Like I said it's a negligable amount and not one that's likely to make any difference when you're trying to calculate your range
I'm happy now just to fill up when the range goes blank. No need to keep on going when I've already got a 500 mile tank under my belt which was my goal all along
Like I said it's a negligable amount and not one that's likely to make any difference when you're trying to calculate your range
I'm happy now just to fill up when the range goes blank. No need to keep on going when I've already got a 500 mile tank under my belt which was my goal all along
Yes i meant for me, when I attempt my 400 mile tank!
OP
OP
Apparently you'd need 42.72 for a 400 mile tank.Yes i meant for me, when I attempt my 400 mile tank!
Do-able then. I nearly did it before with 368 miles/42.5 MPG remember, i just chickened out a bit with the fuel! One day maybe...
OP
OP
Just use your brain (unlike I did) and carry 5l of fuel in a tank
The tank and all fuel system is sealed. This is a EC emissions regulations requirement. There will always be a vacuum in the tank due to taking fuel out of it of course. The pressure is regulated to a very low vacuum by a valve that has the vapour pass into the "charcoal canister" where it sits until that gets filled up. The fuel vapour is then discretely passed into the intake for burning at intervals via another solenoid driven valve to prevent any build up of pressure and to ensure there is little or no emission of naughty petrol vapour, hence little to no parp when opening cap of well working car. Your previous cars have had partially blocked/totally blocked/broken/non-existent emission control systems by the sounds of it.
At the risk of this thread spiralling off into the argument woods
So what's the issue with having less vapour space? Would not that valve operate as usual (all be it more often if less vapour space) to relieve the vacuum? (As long as there is enough to prevent the cannister being flooded, obviously
) I guess the cannister is nominally maintained at intake manifold (ergo, vacuum ish, lower than fuel tank pressure) pressure?Is there a site somewhere with an explanation (ie. pretty pictures!) of this system, I guess it's fairly generic these days.
I suspect the previous cars maxi and have had did have a sealed tank, but with less stringent emission requirements weren't required to have the valves or cannister (it was probably good enough to not vent whilst driving or allowed whilst filling up or similar. Although, relieving a vacuum in the tank would not release large amounts of fumes I imagine, especially if a pump nozzle was soon to be inserted*).
*ooer missus
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I think you're right about older cars exhibiting more parp and not being fitted with any emissions control, but it has surprised me how many 90s cars I have had that simply don't work or are blocked, ultimately causing the "too much vacuum to actually draw fuel" issue, which can only be relieved by undoing the fuel cap.At the risk of this thread spiralling off into the argument woods
So what's the issue with having less vapour space? Would not that valve operate as usual (all be it more often if less vapour space) to relieve the vacuum? (As long as there is enough to prevent the cannister being flooded, obviously
Is there a site somewhere with an explanation (ie. pretty pictures!) of this system, I guess it's fairly generic these days.
I suspect the previous cars maxi and have had did have a sealed tank, but with less stringent emission requirements weren't required to have the valves or cannister (it was probably good enough to not vent whilst driving or allowed whilst filling up or similar. Although, relieving a vacuum in the tank would not release large amounts of fumes I imagine, especially if a pump nozzle was soon to be inserted*).
*ooer missus
I haven't thoroughly absorbed the whole thread or anything and I certainly don't know everything about these systems or the history of their evolution, I just didn't want to leave something I know to be factually incorrect left on the board (no offence 306maxi!). I rarely argue with someone's opinion in forums for the sake of it, so this is unlikely to turn ugly!
My guess on the overfill issue, is that the fuel vapour pipes that run in parallel to the filler tube and enter it near the top to allow the pressure stabilisation to take place don't want to be filled up with petrol. I can imagine that when a valve opens to release some vapour, only to find petrol coming right back at it, there may be undesirable effects. Dunno?
Other obvious issue as mentioned before is that freshly filled car left in heat can cause petrol to expand to the point of nowhere to go, although the fuel cap or a line would fail before the tank of course. This has happened to me a couple of times actually with the Panda since being on Fuelly! The last time it happened, it had been cold and on only a moderately warm day, fuel was pouring out of the safety pressure release valve in the fuel cap. I had even driven a few miles after filling as I was weary about a previous experience. I put it down to fuel being very cold underground and me filling a WHOLE tank and then of course leaving the car in direct sun.
I'm happy now just to fill up when the range goes blank. No need to keep on going when I've already got a 500 mile tank under my belt which was my goal all along
Of course, if what we know/believe from comparing speedo readings to GPS readings (in my case anyway) that they can be up to 10% over, then, if one had his pedantic hat on (not me of course, lol) one could perhaps intimate that you had only achieved a 450 mile tank. 
As I said awhile ago, modern fuel systems are complex and require a vapour space to work properly.
Think about what would happen if you managed your lubrication system this way. First, you pour oil into the engine until it comes up to the top of the dipstick hole. Then, ignoring any warning lights or other messages you might see, you just keep using the car until it stops at the side of the road through oil starvation. Think of all the time you'd save by not having to check the oil!
That scernario is quite obviously just plain silly - but IMO it's also silly to treat your fuel system this way.
Think about what would happen if you managed your lubrication system this way. First, you pour oil into the engine until it comes up to the top of the dipstick hole. Then, ignoring any warning lights or other messages you might see, you just keep using the car until it stops at the side of the road through oil starvation. Think of all the time you'd save by not having to check the oil!
That scernario is quite obviously just plain silly - but IMO it's also silly to treat your fuel system this way.
OP
OP
I hate you
So it finally happened. 2 tenths away from the petrol station and the car starts spluttering, then the engine cuts out! Luckily it was slightly downhill so clutch in and i cruised the rest of the way there with my hazards on! How lucky, had to explain to the guy behind though, think he thought i hit black ice!
Anyway, assuming the tank was empty, i brimmed it until i could see fuel sitting in the nozzle end. 39.02 litres?! Not as much as Maxi got in. So what gives? I'm guessing it's the fact that it's a different pump etc, thing is,. I've always used this pump and i've had 40+ litres in before without running out. So either they need to re-calibrate their pumps, or the computer on the car is a little inconsistent!
Here are the stats though, pretty good for an Abarth!
352.6 Miles (2nd best tank, 368 was my best) 39.02 litres to brim and 41.1 MPG
Anyway, assuming the tank was empty, i brimmed it until i could see fuel sitting in the nozzle end. 39.02 litres?! Not as much as Maxi got in. So what gives? I'm guessing it's the fact that it's a different pump etc, thing is,. I've always used this pump and i've had 40+ litres in before without running out. So either they need to re-calibrate their pumps, or the computer on the car is a little inconsistent!
Here are the stats though, pretty good for an Abarth!
352.6 Miles (2nd best tank, 368 was my best) 39.02 litres to brim and 41.1 MPG
OP
OP
Interesting. I've quite a few 40 and 41 litre fuel ups from various different petrol stations so someone's petrol station is over or undercharging them I guess!
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That is interesting - I know pumps are calibrated and checked (by Trading Standards I recall?), but how often? One would think that most pumps are modern and sophisticated enough not to go out of whack at all...
Does anyone know anyone who is a producer on Watchdog? Might be an interesting investigation - especially now that fuel costs about a billion pounds a splash.
Well if i filled it before when it wasn't quite empty and it was 40 litres, and now it's 39 when empty, then i'm not saying a thing!
