Well, in an attempt to see if 400 miles from a single tank is possible from a 1.8T Octavia I've been driving below 2500rpm, lifting off 1/2 mile before junctions and driving along with the instantaneous MPG trip displayed.

A week later and I've done 184 miles, the trip is predicting just 185 miles remaining. Considering I used to get 300-320 miles by driving normally its confirming my previous thoughts that something is wrong with my car :confused:

Once it gets down to around 5 miles remaining I'll fill it up and manually work out the MPG. I'm hoping the fuel sender is at fault and there is actually more fuel in there than it thinks (thought it still costs

I can still get to 60 in under 10 seconds keeping below 2500rpm.

Hope in the long run, you find out what's causing the lack-lustre economy.

Its not all doom and gloom though, in order to save fuel accelerating out of corners I've been going round some bends at rather interesting speeds

My old vRS remapped could manage 400 miles on a steady run but usually around 360. The mondeo 2.0 does about 430 before needing another £50 of fuel. The boxster is about 320ish, for a 3.2L NA engine.

My currnet thoughta are that it could be tyre related. I'll be fitting some Toyo Proxes T1-R's at the end of the month and maybe that'll help.

I find driving at 3000rpm rather than 2500 tends to yield better MPG in the long run...not sure if it's the same for the 1.8T though...

Rob.

I just stare intently at the instantaneous trip and adjust my right foot to ensurre it is above 30 MPG where possible.

:eek:

Have had at least 420 miles from a tank, and that's without any conscious effort to preserve economy. If you have the instantaneous trip visible, you should be able to keep it in the 40s normally, except on hills, at speeds up to 80 mph or so.

:eek:

Nick - your car isn't remapped though, is it ?

Last night the only time the trip showed over 40 was when I was slowing for junctions etc. Even maintaining speed on a level stretch of road never gets above 38 MPG in recent weeks.

I usually do 100% of my weekly driving in town and Ive rarely bettered 300 miles. Saying that though I never see less than 280 in town. On the motorway at a steady legal speed cruise I see in excess of 400miles from a tank, usually nearer 430 miles.

The car runs a jabba 1 bar remap and has a number of other mods also.

Lee

No, it isn't remapped. But my old one, which was, achieved about the same MPG. Admittedly the 4bar FPR in the new one may have skewed the trip figures somewhat, but it's still much more economical than 30 mpg, without even trying.

Stickier tyres (and balancing, and alignment) do hurt fuel economy. May be worth having some checks done ...

errrr..... that is a little unrelated to what this thread is all about - dont you think?

There is a section on here for saying "hello" perhaps a mod coul dmove your message over there?

errrr..... that is a little unrelated to what this thread is all about - dont you think?

There is a section on here for saying "hello" perhaps a mod coul dmove your message over there?

Have moved post, that will confuse things.

My remapped vRS (as below) will approach the 40 mpg average on a return trip to visit the outlaws in Inverness. That's up the A9 and back down the A82 using cruise as much as possible. :)

Running on 97 RON Tesco super unleaded.

And just to show that I'm not pussyfooting, the average speed varies between 59 mph and 61 mph. Only about 20% is on dual carrigeways :D

Perhaps it is something to do with my map? I remember when i changed the plugs in january they looked like it was running quite rich.

However, I think I would have noticed it before now as its been remapped for just over a year.

My similarly Jabba'd 4X4 Estate averaged 31.27 mpg over 6921 miles prior to the remap and 31.90 mpg over 9589 miles since - the latter period running on Optimax/Ultimate. Do you have access to VAG-COM to check that the MAF readings are OK?

I have a vag-com serial cable but no longer a laptop with a serial port :(

I do sometimes have slight "hunting" around idle speed, its not much - about 50rpm I guess. I've wondered before if that could be a MAF related issue.

How would the MAF affect the MPG ?

EDIT: Reading on both seatcupra.net and UK-MKIV's it seems a faulty MAF is often a cause for low MPG, as is a faulty coolant sensor.

I think I need ot find a laptop with a serial connector I can borrow for the evening........

Of course a faulty MAF could be the cause - it's the primary sensor used by the ECU to work out air/fuel ratios. Try and find someone who'll swap their MAF over for a little while.

We shouldn't forget yours is a 4x4 Goochie - you will suffer somewhat in the mpg stakes due to higher transmission losses.

Denis - 16.5k miles in 4? years? you need to get out more!

We shouldn't forget yours is a 4x4 Goochie - you will suffer somewhat in the mpg stakes due to higher transmission losses.

Although due to the nature of Haldex surely the losses wouldn't be that high, as it will be operating as a 2WD most of the time?

Rob.

Agreed, but still some - you have to drive the portion of the transmission up to and including the Haldex.

I thought that lambda sensors are also used for fuel/air monitoring, not just MAF - MAF is to guage airflow in, and o2 sensors to measure unused fuel coming out..?

As you say, a dodgy temp sensor can cause rich running as it always thinks the engine is cold. Really old and dirty air filters can do it too, although I've never heard of that being a problem on the VAG cars.

(And I didn't think Phil's car was 4x4 ..?).

Re 4x4 - I thought it was? Apologies if this is not the case.

Yes, O2 sensors used as well, but I think they are only a fine adjustment.

I wonder if a dodgy temp sensor could also cause "lean" running :rubchin:

Its true - my car in not a 4x4 :( (hence bengie's fast get away in the videos)

I've sourced a laptop I can use at the weekend that does have a serial port, having seen some logs over on cupranet of MAF air flow readings so hopefully I can shed some light on it by monitoring that.

I assume the coolant temp sensor is cheap and easy to change? I did notice the other day that the car took nearly 2 miles of steady 30mph running (including stops to let traffic through calming measures) to reach normal running temperature, I put this down to the cold weather we've been having lately but I suppose that could be related.

Mine takes from my house to the other side of J16 in the mornings to reach temp - that's about the same distance.

Apologies for introducing the 4x4 red herring.

having seen some logs over on cupranet

:naughty:

I wonder if I beat Bengie to it