Mpg Question Again

[dave32]

What do people generally get? I'm looking to hear especially from sport owners as I generally get between 30-35 mpg which for a diesel is dire. I do 45 miles a day and 35 of them are dual carriageway cruising at 75mpg. It's had a full service in the last 3 miles including the fuel filter and I do use red ex about once a month

[Steve_M]

You get about the same as me for a very similar journey. mine was serviced in july and I don't use additives.

[999101999]

I drive 14 miles to and from work each day( Not on any major A Roads) and if I drive my 220D like a milk float I can get 42/44 mpg according to the on board fuel economy calculator !! If I drive in a traditional manner and don't use 6th gear then 37 is the usual. !!!! My 220D is well serviced, EGR cleaned and generally very well maintained. Great car but far from the best on MPG for a diesel. My next Lexus will be a petrol 250 but I really do like the 220D.

[Mouser]

It's very distance dependent in my experience, but for normal driving I'd expect the IS250 to return roughly:

1-3 miles ~25 mpg

< 10 miles ~ 30 mpg

< 20 miles ~ 35 mpg

< 40 miles ~ 40 mpg

long & slow ~ 45 mpg

[johnatg]

You must drive with a very light foot! I've never seen better than 35mpg and usually about 31.

50% on motorways with cruise set to - ahem - indicated 78 or so - much less in reality of course!!!!

[BillyCam]

Just drove from Harrogte to Aberdeen yesterday and got 37.6 driving at 78 on motorway and sticking to the speed limit on all other dual carriageways and A roads from an F sport.. Not bad at all... Took my time on the way back as I got 3 points on the way down !

[dave32]

It's pretty pants compared to most diesels. You get alot more from BMW or audi

[Steve_M]

you can get better mpg from a diesel jaguar, and that's saying something.

[999101999]

I am looking to change my 2007 for a 2010/11 lower Co derivative so hoping that the MPG will improve and the lower road fund fee would be a positive as well ! Has anyone gone from older to newer and seen any significant change ?

[Steve_L]

I changed up twice and didn't really notice much difference in mpg. Biggest difference was found in move from 220 to 200d. Although it still performed well, the downgraded engine was noticeably more sluggish and not well matched to the 6 speed box.

[Fishboy]

40mpg from the 250!!! Down hill in neutral maybe. Over 20k mine has averaged 33, best ever was 37. These are real figures, the computer reads 2.5 mpg over

[is200 Newbie]

MPG definitely depends how it is driven and how the car is maintained

[johnatg]

That's true. However, pussyfooting around isn't necesarily the best policy.

One of the problems that car manufacturers have is testing for the real world as their test vehicles inevitably get driven fairly hard during the relatively short test period before release. So problems relating to hard driving are found and fixed - but they often don't find problems which might arise with a car which is driven very softly - eg. two miles in the morning and two miles home in the evening, all at 30mph.

For example., diesel cars are best suited to use for long motorway thrashes. Then combustion is pretty much complete for the great majority of the time and DPF regeneration gets plenty of opportunity. A diesel car which is used for short journeys, never gets properly warm or never driven at speed will clog its DPF in no time. I'm sure part of the DPF problem generally is that manufacturers didn't find it during development testing.

Similarly with direct injection petrol engines (eg IS250). Reading the copious amount of information on this subject, it is clear that carbon build up on the inlet valves is related not only to fuel and oil, but also to how the car is driven. It is more likely if the car is not driven hard. I'm sure a lot of IS250s never get above 2500rpm, especially autos. Use those paddles, hit the red line every so often (or at least get into the orange) and maybe you will never see carbon build up occur!

Won't do much for fuel economy, but might save a lot of money and grief over a car's lifetime!

[steveledzep]

Very good points John. Mine will probably never go above 2,500 rpm as I normally drive it. I'll give those paddles a flex tomorrow !

[dpz46]

40mpg from the 250!!! Down hill in neutral maybe. Over 20k mine has averaged 33, best ever was 37. These are real figures, the computer reads 2.5 mpg over

If that is true then the computer on mine read 44.6mpg at 70mph (Cruise) going up the A1 so 2.5 off that would still be 42.

When i got through to the road works which was a 50mph limit it dropped to 38mpg. As i said before i'm lucky to get 26-28 around town though.

[Fishboy]

The only way to get the real mpg is working it out with each tank full and then average it out over time. The longer you have the car the more realistic the figure. If you get chance google fuelly

[Dean8788]

My IS250 around town is about 24mpg on a run 37mpg, the best I had was 44mpg. However when I had the GS300, I went to Belgium and got 46.7mpg not bad for a 3.0 :)

[aly-g]

I've got to get a smaller right boot, I get 19/20 mpg driving locally and about 32mpg on a good run, it's all relative though. You don't buy a lexus for economy do you ????

Allan

[toffee_pie]

with this winter weather them 500 mile tank ranges on a i250 will be a pipe dream, my economy i notice has taken a nose dive i notice recently, crap city driving and cold starts, the car is hardly heated up when i turn it off again. not too surprised.

[steveledzep]

My Lexus is very new to me and it's noticeable that it takes a while to come to operating temperature. My commute to work is only 5 miles at 30 or 40 mph and the motor's not at normal temperature when I arrive ! My previous Saab was up to normal by half way. More mass in the block I guess being a V6.

Anyway, can't be good for economy. Since the last fill up, my computer is showing 29mpg, that's about 10 commutes to and from work with one 40 mile round trip to the supermarket.....so not too bad ! Saab was doing 27mpg. Yes, you read correctly, tidy supermarket is 20 miles away ! It's bliss here !!!!