46.19 Litres is a 42 Litre tank???

JIGSAW

Banned
if you were nearly out of go go and you filled her to the brim id say nothings amiss .. as the filler neck is quite a large diameter and travels just under 1 meter into the top of the tank so could hold the extra amount .. id also imagine the measured volume of the tank is prob not full to its maximums
 

Muska

A2OC Donor
What size is the smaller tank? I usually get about 32l into mine when brimming it. Also, are the tanks interchangable?
 

67boris

A2OC Donor
There is a vent flap to the right couple of centimeters from the top of the filler neck. If it's kept open while refueling, it will also fill up with fuel, hence the increased capacity. Here in Cyprus is almost a common practice to do it, as pump employees think you must fill all crevices to be considered a full tank.

Boris
 

JIGSAW

Banned
i think theres 3 sizes of tank 32L 34L and 42L they could be swapped over but its not as simple as just swapping the tank , as sure the instrument cluster is also mated as such to tank size along with the fuel pick up and level sender
 

Catnip64

A2OC Donor
i think theres 3 sizes of tank 32L 34L and 42L they could be swapped over but its not as simple as just swapping the tank , as sure the instrument cluster is also mated as such to tank size along with the fuel pick up and level sender
Don't forget the exhaust either, since this is routed around the 'corner' of the larger tank it would need to be changed as well.
Are the mounts the same for both tanks?

Steve
 

DJ 190

A2OC Donor
i think theres 3 sizes of tank 32L 34L and 42L they could be swapped over but its not as simple as just swapping the tank , as sure the instrument cluster is also mated as such to tank size along with the fuel pick up and level sender
I'm not sure that there's any great advantage in fitting the larger tank? I can easily cover over 350 miles with my full 32 L tank. There's plenty of filling stations and it's no great chore to fill up? I have an LPG powered Mercedes SLK. IT does around 220 miles on its tank of LPG AND there isn't that many stations selling LPG! There .... both ends of the Spectrum! LOL!

David
 

Muska

A2OC Donor
It would mean less trips to the fuel station for me. I get around 420-450 from my smaller tank but more is always better as that lasts me about 1 fill up a week generally.
 

AndyP

Member
Whilst a larger tank initially sounds like a good idea (and I'm quite happy that mine has the 42l) the extra weight will reduce acceleration and fuel economy, so I'd guess that the super efficient 1.2 diesel has the smaller tank (unless it was essential for the long distance test Audi did).
 
yeah, my 1.2TDI only has room for 21L of diesel (like most other 1.2), you can squeeze in a couple liters more if you fill it all the way, and also hold the little valve open so the ventilation tube is filled as well. Even though the tank is only 21L i get 6-700km on one tank depending on driving style.
 

DJ 190

A2OC Donor
Even though the tank is only 21L i get 6-700km on one tank depending on driving style.
Yes, then when it was stated to be the first "3 litre" car to go into mass production, you're saying that it's a fact! (3L fuel per 100km) That's a LONG way to go on so little fuel!

David
 

audifan

A2OC Donor
Please be careful if using the tank vent method to squeeze more fuel into the tank. That air space IS NEEDED IN PETROL ENGINE VERSIONS TO ALLOW SPACE FOR THE FUEL VAPOUR. The diesel however does not need this air space so can safely be filled by this method if you choose. Biggest problem is the modern pumps delivery rate is higher which causes foaming in the tank and cuts off the pump early due to the back pressure. If you can slowly fill or as Ben has just said fill from jerrycans the slower fill rate lets the air escape allowing more fuel in.
 
forgot to say it is a diesel, im aware you cannot do this in petrols, curiosity got to me thanks for the heads up
 
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audifan

A2OC Donor
Tank size changing is not straight forward. The 1.2 can not EASILY be retrofitted with a larger tank, While the 34 / 42 shares the same mountings the rear exhaust section routes differently and some brackets are in a different location. Add to that the instrument cluster is I believe hard coded to the fuel tank size and the polarity is reversed to the gauge. Even with a very heavy right foot these are still very economical cars that a lot of far more modern vehicles struggle to match let alone beat. Everyone drives the way they want to either to get maximum range per tank or play with far bigger cars in the fast lane, that is there choice. In short the gauge is directly connected to your right foot, and by changing slightly you may improve economy assuming the car is well serviced and does not have issues like binding brakes , a top box or is towing. I like my happy medium that returns about 47 mpg and I am happy with that. Same driving style in a 1.6 petrol cavalier returned 23 mpg!!!!!!
 

depronman

A2OC Donor
Tank size changing is not straight forward. The 1.2 can not EASILY be retrofitted with a larger tank, While the 34 / 42 shares the same mountings the rear exhaust section routes differently and some brackets are in a different location. Add to that the instrument cluster is I believe hard coded to the fuel tank size and the polarity is reversed to the gauge. Even with a very heavy right foot these are still very economical cars that a lot of far more modern vehicles struggle to match let alone beat. Everyone drives the way they want to either to get maximum range per tank or play with far bigger cars in the fast lane, that is there choice. In short the gauge is directly connected to your right foot, and by changing slightly you may improve economy assuming the car is well serviced and does not have issues like binding brakes , a top box or is towing. I like my happy medium that returns about 47 mpg and I am happy with that. Same driving style in a 1.6 petrol cavalier returned 23 mpg!!!!!!
I looked into a 34 to 42 litre tank swap some time ago (decided it was not worth the effort) but just for clarity there is a error in 'Audifan' details above.
It is true that the tank sender was reversed sometime in 2003, but this did not align with the change to the 42 litre tank, there was about 3 to 4 months of 34 litre tanks that had the fuel gauge / tank sender units that work the opposite way around to the earlier A2's i.e the same as all of the 42 litre tanks.
Please don't take this as nit picking, just making the facts public as it could cause someone grief trying to figure out why a second hand tank sender unit reads the wrong way. It is possible (well at least for Timmus) to re program the instrument cluster to correct the fuel gauge reading the wrong way around
Cheers,
 
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