I'm after some advice regarding fuel consumption in my 1.4 tsi dsg 66 plate, I got the car in August and the fuel consumption seems appalling,  at least according to my fuel gauge. I did 44 miles this morning of mixed driving, the gauge was very slightly below halfway, when I got home it seemed to have dropped much more than I would expect, I have attached a photo of how much it had dropped.  I did previously have a diesel car so perhaps I'm just not used to a petrol consumption.

I have often seen as have others, that a full to the brim tank that the needle will not move from F for a long time, once it starts moving it will move steady to 1/2 tank.  Below 1/2 a tank I find it seems to accelerate.

 

It's about tank curve profiles in software and other VAG such settings like that I would say.

 

 

Only good way to measure consumption is brim to brim filling for accurate figures.

 

Of course the car needs tyres inflated to correct values and servicing done on engine/dsg for it to achieve a sensible mpg.

My previous 1.4TSI manual averaged 45mpg, so with a DSG you should get nearer to 50mpg (or better).

 

Remember than fuel gauges are VERY non-linear, on the Octavia it barely moves from full for nearly 100 miles then falls slowly to about half and then accelerates - so I would not be making any assumptions on fuel consumption based solely on starting at a gauge showing half full. Wait until you have a full tank and then do a full to full test.

That all makes sense,  it does stick on full for an unsually long time, all the basics are covered, servicing, tyres etc. My average mpg varies, mainly urban I get around 28-35mpg. 40mpg on a run according to what it tells me.

Both our cars bomb for the last 1/3 of a tank - even mine, with its virtual cockpit 🙄

 

I use Fuelly to get brim to brim actual readings.

 

Gaz

I'm hoping it is due to inaccuracy,  because I could shed a tear with the current mpg!

Just now, claire83 said:

I'm hoping it is due to inaccuracy

Well, it's more non-linearity in the gauge than inaccuracy as such. If your model has a trip mileage readout, I suggest filling the tank, zeroing the trip and then leaving it until the next fill, at which point you note the actual mileage achieved and re-zero the trip.

I'll do that, thanks

Please note - I am not a mechanic or expert in anything.

 

Treat the gauge as just a 'gauge' and not an 'accurate'.  Same for the car's own computer MPG figures, think of it as being more optimistic than pessimistic, or exaggerating a little rather than understate.

 

As has been put a more reliable measure is to fill the tank until the petrol station pump clicks off, do not try to add more, zero your tripometer.   Next time you go to the petrol station fill the tank until the petrol station pump clicks off, take the tripomter reading, zero if you want to repeat.

 

If you want MPG then divide the number of litres by 4.54 (or 4.5 if you want) to get to how many gallons and then divide the number of gallons into the tripometer mileage and you have a more accurate MPG which is repeatable for comparisons.

 

Unless someone else uses the same system in the same way take any MPG claims with caution and bear in mind any comparisons are only rough comparisons as there are so many variables.

 

Edited 1 December, 20223 yr by nta16
ETA: Please note - I am not a mechanic or expert in anything.

Please note - I am not a mechanic or expert in anything.

 

1 hour ago, varooom said:

Of course the car needs tyres inflated to correct values and servicing done on engine/dsg for it to achieve a sensible mpg.

To that I'd add carrying unnecessary weight, things like stuff in the car that's carried but not used (junk, tools, spares, undelivered items, perhaps partner or grown kids(?)) and things that reduce the aerodynamics of the car like empty or full top boxes perhaps.

 

I've come from a 2.0 Diesel to a 2.0 Petrol so like the OP still try to adjust to the fuel consumption rate.

I've also noted that the 2nd half of the tank goes a lot quicker than the first. Same on my last VAG car, putting it down as a "feature"