55 astra 1.8 sri - darrenmc
Hi just baught this canr about a month ago got rid of my punto hgt spent tooooo much time in garage only had tht 10 month got it from new......

so i thought id get an astra.. mmm

started well but

im getting only 31 mpg on moterway vauxhall say sold be doing between 40 and 45 mpg.

I get better mpg using the sport mode?? If i dont use sport mode then the car because very jerky not very responsive at all judders between first and second gear.

alarm kept setting its self of - thts been fixed wth software update they did updates for the above but hey acording to the fuel comp im gettin 30 mpg average so when i put 10 quid in i get 70mpg if im lucky.... about 300miles per tank?? my frends for mondeo st 220 gas drinker does more mpg on moterway..

can anyone help me please is this normal (not according to vauxhall data sheets) thought astras were quite reliable???

Thanks for lookin

daz
55 astra 1.8 sri - blue_haddock
The engine will require running in - until it is fully run in it will use more than the stated amounts.
55 astra 1.8 sri - Dynamic Dave
And the stated amounts are just that - stated. Real life is different to laboratory conditions, which stated figures are calculated from.
55 astra 1.8 sri - Red Baron
It's news to me that the manufacturer quotes fuel consumption figures for the Motorway. I thought they only quoted urban (30ish ?) extra urban (56ish?) and combined.

40 - 45mpg for a 1.8 sounds utopian at 70 - 75mph.

For this car I think you'll get 35 - 40 mpg at those speeds. How many miles has the car done? Ought to be run in by now really.
55 astra 1.8 sri - Dynamic Dave
Figures for a 1.8 manual

Urban driving 26.6 mpg
Extra-urban driving 44.8 mpg
Combined figure 35.8 mpg
55 astra 1.8 sri - Altea Ego
he mentioned sport mode?

is it an auto?
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TourVanMan TM < Ex RF >
55 astra 1.8 sri - cheddar
I assumed it is an auto from the OP.
55 astra 1.8 sri - darrenmc
no its a manual and it has done 14000 miles it has sport button.... like i said dos more miles per gallon with it on as for figures te rods near me have 50 limit and i spend most of my time going to work on this road and there is not much traffic when i do
55 astra 1.8 sri - cheddar
So what does the sport button do?
55 astra 1.8 sri - darrenmc
the sport button makes it go faster and stiffens up the suspension...
55 astra 1.8 sri - LeePower
I had a 06 plate 1.8 Astra SRI hire car the other week, Only 2.5K miles on the clock, Aircon & sport mode on all the time, I hope the poor mpg was down to the engine running in still.

It drank the petrol, Put it this way I wouldnt want to own one the way it was eating my money having to keep filling it up, Ive never known a car drink so much fuel lol

55 astra 1.8 sri - darrenmc
well i took it to garage put in ten quid... then said on comp had 110 miles left... took it on a run 60 all the way apart from roundabout when i got home after 12 mile run then said i only had 70 miles left?? its booked in for a whole week next week in vauxhall garage..... fuel problem they say just does not run smooth when driving u loose power bet 1 and 2nd and with sport button on now insed of bein smooth feels flat then u get sudden boost of power as if turbo (no turbo) kicks in....
55 astra 1.8 sri - Dynamic Dave
well i took it to garage put in ten quid... then said on comp had 110 miles left...


And there lies your problem. You're calculating the mpg from the computer and only adding a splash of fuel to the tank. Fuel computers are a novelty, but often don't give accurate readings. That aside, you need to do at least 15 miles before the miles left figure gives anything half sensible.

What you need to do is to brim the tank, reset the trip, and then do a couple of hundred miles and then rebrim the tank again, and then get the calulator out and work out the mpg accurately from the amount of fuel you've put in and the total mileage covered.

For now I would cancel the appointment with Vauxhall, before they charge you with wasting their time.
55 astra 1.8 sri - darrenmc
CHARGE ME I DNT THINK SO..... I also took the miles i had done FROM THE fuel gauge which fell like a stone in the water...... and the mile omiter which i had reset....
55 astra 1.8 sri - Caveman
CHARGE ME I DNT THINK SO..... I also took the miles
i had done FROM THE fuel gauge which fell like a
stone in the water...... and the mile omiter which i had
reset....


As has already been pointed out, brim the tank, - etc, then do the calculation. At the moment you're just guestimating the mpg by your current method.

I'm suprised the garage haven't told you this. well actually I'm not suprised because if they cannot find anyhing wrong with the fuel consumption, then they will more than likely charge you because no fault was found.
55 astra 1.8 sri - Dynamic Dave
CHARGE ME I DNT THINK SO..... I also took the miles i had done FROM THE fuel gauge


Very accurate calculation then, taking the miles you had done from the gauge?
which fell like a stone in the water...... and the mile omiter which i had reset....


Your earlier post said you put £10 in. So, just over 2 gallons then. I'm surprised the gauge moved enough for you to see the difference, to be honest.

Yes, I can't see the garage charging you for the other problems, but with regard to the MPG query, unless you accurately calculate it, (and not rely on what the gauge or the fuel computer says).... be prepared to get your wallet out.
55 astra 1.8 sri - John S
Darren

I have the previous model 1.8 Astra, which has, I believe, the same engine. Fuel consumption was never as low as 31 on the motorway - probably 35 at worst, and that was fully loaded. It took over 10,000 miles to run in fully, and now does 38 or more on long runs.

Early on the car did develop a definite hestiation at low revs - it jerked badly when it was asked to pick up between 1500 and 2000 revs which made traffic driving a pain. The dealer downloaded revised software to the ECU which completely cured it. Certainly worth going back to the dealer and enquiring.

JS
55 astra 1.8 sri - darrenmc
yes thts wht iv got the hesitation.. its had software update no luck going in for a week next week for diagnosics.... its hit and mis with the car as today it was doing 36 mpg on a short 10 mile run... most ive ever seen.... but then on way home the car would not start... started and then turned its self off tried again... nothing it was dead.... left for a min then started.. but became jerky again when changing gear from first and second...... so hey there u go another day wth the astra.... and i thought it wud b more reliable than my punto hgt
55 astra 1.8 sri - landmarked
What is it with Vauxhall and naff ECUs? I remember back in 1989 reading an issue of What Car? where they took their long term 2.0 injection MK3 to be 'chipped' - in those days stil a somewhat novel notion. It stopped the car kangarooing in traffic, improved the responsed and upped the economy!
55 astra 1.8 sri - darrenmc
well its in garage for a week now.. it cut out on me yes day
55 astra 1.8 sri - Dynamic Dave
well its in garage for a week now..


And one week later, what's the verdict then?
55 astra 1.8 sri - darrenmc
hi and thanks... yes got it back last week its had even more software updates and it has taken care of the judder... they said the computer was set up for a different fuel tank??? something todo with a sterer?? i dont know but hey im now getting 200 miles per half tank.. have tested it by the comp which seams to be acurate but also by the car mile trip computer...

any way all seams well.. for now and thanks all for your sugestions
 

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