Just gone 140 miles round trip to pick up a milltek system and I end up with 46MPG and that was loads of gear 5-6 cruising.

Driving around I usually get like 32-34 as well, seems I'm like 10mpg lower than people.

175 revo map

Egr delete

Back box delete

Edited 14 February, 201610 yr by AdamOP94

Just gone 140 miles round trip to pick up a milltek system and I end up with 46MPG and that was loads of gear 5-6 cruising.

Driving around I usually get like 32-34 as well, seems I'm like 10mpg lower than people.

 

Don't trust the mpg reading - can be pessimistic as well as optimistic (my Superb I under read by 4 mpg). Measure full tank to full tank or if you are as sad as me use something like Spiritmonitor (click on the link in my signature below) or Fuelly

Edited 14 February, 201610 yr by bigjohn

Doing a full service helps, all filters etc. You could have a brake binding, tyre pressures all correct? When I went up to snetterton I was doing 60/70 all the way and got 72mpg. My read out was stating 70 mpg.

Don't trust the mpg reading - can be pessimistic as well as optimistic (my Superb I under read by 4 mpg). Measure full tank to full tank or if you are as sad as me use something like Spiritmonitor (click on the link in my signature below) or Fuelly

I also reset my gauge when I full up, get 60-70 miles before fuel light comes back on per £10

@service, doing one soon

As above,work it out correctly,don't get hung up on your dash figures.

When you fill it up make a note of the litres put in,reset trip mileage,run it down to empty again and note the miles covered.

Divide the litres put in by 4.54,this will give you the gallons of fuel,divide the mileage you got out of the tank by the amount of gallons,this will give you your true mpg.

Edited 14 February, 201610 yr by coskev

I think his problem is more, everyone els with the same car is reading higher than his.

Could be a faulty air flow meter.

As said, full service will help, good tyres with correct tyre pressures make a difference.

A bad remap will affect it a lot as well. Jamie6yfabia on here got his remapped recently and now doesn't see over 45mpg on a long run, used to be mid 50's

Edited 14 February, 201610 yr by hutchysrs50

Could just be he's got a heavy right foot too.......

All the extra H20 carried (very heavy water.) that is leaking into the car will maybe be the cause.

 

 

 

 

Then maybe the Remap and other tuning enhancements are not having the car run as efficiently as standard.

If they are working well and you are enjoying spirited driving it might not be the same as economic driving or even hypermiling.

Edited 14 February, 201610 yr by GoneOffskiroottoot

I'd put it down to the remap. Or driving style.

Tank to tank, brim to brim will be your best measuring method.

JRJG

I'd think, if he continues using the same method of gauging MPG, he needs to buy fuel from a cheaper outlet (more miles for £10 ?)

Regarding the price, I don't even know what I pay but when I put £20 in I expect around the 200 mile mark

Lets teach 'grannies to suck eggs'.

 

If you are paying under £1 a litre now you are getting over 4 gallons now for £20.

 

Last year you were getting less than 4 gallons obviously.

The MPG has not improved since the price dropped again rather obviously.

 

So filling by price is hardly telling you much about if your cars economy is dropping.

Despite me making a joking but correct statement, this is maybe the time to say, get to know your car as soon as you buy it as having a good record of fuel usage can help further down the line especially when considering moding the engine, sad to say I've done it with all my cars over the past maybe 40 years - that way I can work out when something is not right. Piling goodies on to a car is okay and up to the individual, but keep an eye on how the car is going at the same time if MPG is important to you.

I do have a heavy foot and getting 32-34 usually.

Today I cruised a lot, did over 100 miles and still only just saw over 45.

I get 60-70 to a tenner and others get 100+ with more power mods. The map I have is to 175bhp but it was a REVO one? I may get it on the dyno when I get my decat to be on the safe side.

I dont even bother with my trip, its never shown above 42mpg, even doing 200 miles to Devon hours at a time sticking to 70  = 41mpg, Birmingham restricted 40miles of 50mph  = 32mpg. When i worked it out as best i could i got 56mpg on the Devon trip @ 70 mph, and 54mpg on the Birmingham stretch. Ive had several maps (standard, 2x different 165 maps, Johns Map) none have been different on the trip. If i cane it trip say 27mpg, if i drive conservatively trip is never more than 42mpg.

 

 - I dont care any more, diesel is cheap. Car does great mpg even driving like a lunatic.

 

I would just forget about it :P 

It's cold and it's been very windy recently. These are huge factors alone.

 

Then there is the heavy right foot, cruising speed, overtaking up hills, rolling down hills, accelerating smoothly, braking gradually... etc. etc.

 

 

 

 

The only way to really know is to have a known trip that you do on a regularly basis and to suddenly start seeing drastic MPG changes. Or to do the full tank-full tank method but driving similarly for all 1000 of those miles.

It's cold and it's been very windy recently. These are huge factors alone.

 

Then there is the heavy right foot, cruising speed, overtaking up hills, rolling down hills, accelerating smoothly, braking gradually... etc. etc.

 

 

 

 

The only way to really know is to have a known trip that you do on a regularly basis and to suddenly start seeing drastic MPG changes. Or to do the full tank-full tank method but driving similarly for all 1000 of those miles.

That about says it all really. I pretty much drive to the same places most of the time so I've been able to observe consistently, I have managed to steadily improve mpg overall since I owned the car. Largely due to a combination of things including consistently using branded fuel, getting used to a diesel, being very steady when in the cold start phase particularly in this weather, and driving to the strengths of the car. My overall trip is steadily reading 59-60 round rural Wales. On the same runs over the first few weeks of ownership (when it was warmer) it was 57-59. I've done a brim to empty calculation and it wasn't far off what the trip read as it goes, reckoned it to high 50s.

At least as said by driving consistently and paying particular attention to how it goes on the routes I know well its easier to spot any anomalies.

Here's a question for the OP, how is your thermostat? If it's sticking you will be running rich, and on the type of runs you're doing you may not be off gas/load for long enough to see the temp gauge drop (a tell tale sign). Just throwing one out there...

I've noticed that if I let my car idle it will then bring down the MPG figure so if you leave it idle frequently then you will notice a lower figure on the screen.