Economy - How many miles do you get out of a full tank?

[CliveP]

Despite what the trip computer says, which is a lot of airy fairy really, I get pretty much 35mpg out of my THP - longer journeys I might hit 40.....I don't care, suits me fine...with 0-60 in just over 7 seconds I think that's pretty good really.

Regards,
Clive.

[DaveB]

I only fill to half, more fuel efficent. Always found if you have a full tank first half goes in the blink of an eye. So half x2 would give me 550 miles (1.6vti)

There's no difference between a full tank & a half full tank in terms of economy!

[Buzz61]

6000 miles now on my e-Hdi and the most I'm managing is 420 miles on a tank, which is why it's going back again a week on Wednesday. If it's not sorted this time they can have it back and I'll look elsewhere.

[cyclone]

There's no difference between a full tank & a half full tank in terms of economy!

Technically a full 50l tank of petrol weighs in at about 80.6 lbs at 60 degrees. So running a half tank would save you 40.3 lbs of weight. Anytime you reduce the weight your engine has to move, with the same driving style, you will get an increase in MPG. Doubt you will notice enough if any improvement to make the practice of just half tanking worth your while though.

[Bigfeet]

6000 miles now on my e-Hdi and the most I'm managing is 420 miles on a tank, which is why it's going back again a week on Wednesday. If it's not sorted this time they can have it back and I'll look elsewhere.

What are you expecting? Please ignore what other people have posted because MPG is no way an exact science as we all drive, change gear different. Even things like tyre pressure and weight in the car has affect. Do not go with the fingers in the brochure as they are NOT to be used for real world driving.

[Dreamsphere]

That is poor from a diesel. I know of someone with a C3 1.6 who returned 74mpg in their first 1400 miles but have no idea of they're driving style. As you can see from my image below my 110 Sport is doing 67.1mpg but as Bigfoot rightly says it's not precise although I have checked the computer against reality (brim to brim filling and it was spot on). As has been mentioned before, harsh acceleration would appear to affect the mpg more than higher speeds (make sense I suppose) but it's all relative.

Good luck!

[chiefnerd]

harsh accelration and braking unnecessarily, changing gears in wrong rev ranges etc...try following the gear indicator precisely and see what happens

[DaveB]

try following the gear indicator precisely and see what happens

You'll probably die of boredom!

[chiefnerd]

Damn right you will. My usual comment is stop looking at the bloody trip computer and just enjoy the car!

[B19PPh]

There's no difference between a full tank & a half full tank in terms of economy!

Cyclone beat me to it. Less weight = Less work for the engine.

Technically a full 50l tank of petrol weighs in at about 80.6 lbs at 60 degrees. So running a half tank would save you 40.3 lbs of weight. Anytime you reduce the weight your engine has to move, with the same driving style, you will get an increase in MPG. Doubt you will notice enough if any improvement to make the practice of just half tanking worth your while though.

It may not be a huge difference but I've run full tank and got less mpg from the first half. All adds up at the end of the day.

[djclark25]

Ive got a 110 HDi and I think I drive pretty economical. I get around 520 miles to a full tank and the trip computer says between 52 and 56 MPG. Whether its as I live in South Wales so not a flat road in sight, as others say they get more out of the same engine.

Only have a bag of cables for work in my boot and I am a svelte 12 and a half stone so not huge weight. Had the car two years and done 32000 miles so far.

[Bigfeet]

Like I was trying to say can we just end this thread as it's a bit pointless. There are so many factors such as air temperature, engine temp, gradients of the road, Air con on or off, what temp your running the Air con, are the wipers running, is there extra drain on the voltage system, are you driving in the rain, driving in the hot sun, etc.

What I'm trying to say is that we could all drive the same car over the same road and we would all return different MPG figures. Just because one person get 60 MPG doesn't mean the rest of us will.

Just drive the DS3 and enjoy it because if MPG was all you're worried about you bought the wrong car!

[DaveB]

It may not be a huge difference but I've run full tank and got less mpg from the first half. All adds up at the end of the day.

For several reasons - location of the sender unit in the tank, geometry of the float arm, shape of the tank, gauge indicating in segments, the fuel gauge is only really a rough guide as to how much fuel you have in the tank, so your comparison isn't really valid - there may be 10-15% difference in actual volume of fuel between the two "halves" you're reading on the gauge!

[AJ07]

Like I was trying to say can we just end this thread as it's a bit pointless. There are so many factors such as air temperature, engine temp, gradients of the road, Air con on or off, what temp your running the Air con, are the wipers running, is there extra drain on the voltage system, are you driving in the rain, driving in the hot sun, etc.

What I'm trying to say is that we could all drive the same car over the same road and we would all return different MPG figures. Just because one person get 60 MPG doesn't mean the rest of us will.


Just drive the DS3 and enjoy it because if MPG was all you're worried about you bought the wrong car!

I am very content with mine, so onwards and upwards!

[Buzz61]

because if MPG was all you're worried about you bought the wrong car!

I've realised that now. Thought downsizing from a 184,000 mile Peugeot 806 2.0 Hdi with a knackered injector would save me money on fuel doing the exact same journeys but obviously not. Went out the other day with friends, me with my 3 kids and 2 friends with their 5 kids in their old Grand Espace 2.2 dt. Same journey, same speeds and he returned 12mpg more than I did. I've been driving diesels since they were fitted in Morris Marina's and also been a mechanic for over 30 years, I know when a car isn't doing what it's meant to do. Couple the piss poor mpg with the flat spots and the fact it won't pull until it's on boost and most people would understand there is a problem. Trouble these days though is unless it throws up a fault code, the workshops haven't a clue and palm you off with bullshit.