Venting the fuel tank

Ibiza 130 tdi

Black Magic
Jan 15, 2007
6,275
1
Somerset
I filled my car up the other day with £30 of diesel. Which ended up being about 27 litres I think. The needle was on 3/4 of a tank when I filled it up yesterday. I vented the tank (not fully - could've vented it more but was getting bored :lol:) and I got another £30 in! :-o

The £30 before took it from 1/4 of a tank to 3/4 of tank. So basically by venting the tank I've got another half a tank in the space where 1/4 of a tank should be.

Last night I drove from Somerset (where I live) to North Lincs (Humber Bridge to be precise) on the vented tank. I did 80 mph pretty much all the way (apart from M1 roadworks and Birmingham average speed check zone where it was both 50 mph) and I AVERAGED 57.9mpg. I thought by venting the tank that I'd knackered the fuel gauge somehow cos it just was not moving!

Anyway - I got here and overall managed to average 57.6mpg (`A' roads and a few blasts knocked it down a bit).

But I managed to do the 250 mile journey on a needles width UNDER a full tank. So used about 30 litres of fuel? I'm guessing.

I took pictures on my phone last night and I will post pictures when I get back to Somerset. I just wanted to brag tbh cos I thought it was amazing how I managed to do the 250 mile treck with the needle moving literally 1-2mm. :D

Does anyone else want to challenge me and beat it? ;)
 

tdi_chris

2012 Leon 1.2 Tsi Copa SE
Apr 6, 2007
180
0
West Bromwich
www.myspace.com
I hadn't heard about fuel tank venting until joining on here. I can't beleive you've managed to do a journey that far with hardly any needle movement!
got any pics of how you've vented your tank?? :D
 

st10587

i only brake for cake!!!!
Oct 4, 2007
3,669
0
Hindhead
if you look down the filler neck on the right hand side there is a little lever (on the inside) push this with the nozzel on the pump and you will hear a 'hissing' sound which is venting the gas out of the tank. i vented mine fully so it was to the brim and got £50ish of diesel in!!

that was from about 1/4 of a tank to full!
 

Ibiza 130 tdi

Black Magic
Jan 15, 2007
6,275
1
Somerset
As said - fill your car up until the pump clicks. On the right hand side of the filler nozzle there is a bit that looks like a little straw. Press that down and you will here a hiss. Fill up til the pump clicks and then vent again. Keep doing this until you can fit no more fuel in!

You shouldn't vent the tank unless you're doing a long jounrey straight after as the fuel won't have any room to expand and you could get in the brown and sticky. ;)
 

st10587

i only brake for cake!!!!
Oct 4, 2007
3,669
0
Hindhead
As said - fill your car up until the pump clicks. On the right hand side of the filler nozzle there is a bit that looks like a little straw. Press that down and you will here a hiss. Fill up til the pump clicks and then vent again. Keep doing this until you can fit no more fuel in!

You shouldn't vent the tank unless you're doing a long jounrey straight after as the fuel won't have any room to expand and you could get in the brown and sticky. ;)

you can just hold the lever down will you fill:whistle:
 

cheshire cat

Full Member
Dec 28, 2002
1,813
1
cheshire
Visit site
or quicker to just remove the valve, search for ventectomy, and please no moaning about spilt diesel (as usual when this comes up) none of us can afford to waste it---well not many :)
 

CHR15B

Active Member
May 5, 2005
2,567
9
Scotland
I don't really vent my tank. Done it a few times but with the miles I do I fill it up with the same amount on the same day each week and it's fine. :)

Would do it if driving a long journey though.
 

Deleted member 13581

Guest
I vented my tank before going to Thruxton last year (800 mileish round trip) and nearly managed it on 1 tank of fuel. Had to fill up about 30/40 miles from home. Was well chuffed with it.

Will be doing it again going to Edition this year.
 

Skisbp

Full Member
feulventvalvekr9.jpg


The requisite pic!!!:whistle:
 

Deleted member 19188

Guest
Most VAG group cars are the same, I vent our Audi A6 too especially before a long journey and can get over 700 miles from a tankful. Don't try this with petrol though, as it can expand when warm more than diesel and therefore leak.
 
Last edited by a moderator:

Slicker

Guest
i've done the same and filled 57litres. and from now one the fuel gauge doesn't show correctly. for example. i made 300km and the needle doesnt't move. yesterday BC shows 30km left i filled 15litres and needle jumped a little bit over half. we will see during next week what went wrong.
 

Skisbp

Full Member
Sounds about right when overfilling, that's what we're essentially doing when venting... It accentuates even further the odd way our fuel gages work. Try looking at miles/kilometers till empty figure as opposed to the gage it's self that even on it's best day would always run 2wice as quick from 1/2 than to it!!!:rolleyes:
 

Deleted member 19188

Guest
I normally fill up as normal, until the first automatic click off of the pump, then vent it, and hold the nossle against the vent lever and continue. I've done about 200 miles since I last filled up doing this and just this morning there is a slight gap from the 'F' on the fuel gauge.

(Nürburgring on Saturday !!)
 
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