Too juicy??

[deeman940]

i would like some opinions please,,,,
i always thought that my 940 was very good on fuel considering it's age and size, but have never really taken it on a long run to determine this.
It was recently in the garage for a year (long story) and had only been started up and moved outside then started and moved in at the end of the day.
when i got it back it was very 'grumpy'...stuttering and wouldn't idle etc (to be expected), Shortly after i took it on a run to Plymouth (240 miles) in which it used the best part of £150 in fuel including driving around down there a bit but not much at all. i thought this was a bit excessive but figured the plugs were coked up after a year of not being run, coupled with smelling slightly rich,
i then changed the plugs to see if this would improve things, i did another run to Plymouth and it fared very slightly better but not a great deal.
i did a run to Birmingham tonight (100 miles) and used £30 each way so roughly the same as the Plymouth run, Since Plymouth the car has had new dizzy cap, rotor arm and HT leads,oil and filter and fuel filter change
does this seem excessive to anyone? i was not using a heavy throttle (80 mph average) and the car has a MBC, air filter and 3" exhaust,
It also seems to bog down in first alot ( running rich??)
Anyone have any ideas?
it could of course all be my imagination and this is the sort of consumption to be expected?!
Damo

[TonyS9]

Its a bit lazy not working out the mpg and expecting us to guess!

80mph is gonna give you about 24mpg in my experience. That should translate to £50 @ £5/gal for your 240mile trip, so yes seems excessive at 3 times. You are talking single figure mpg.

Smelling of fuel could indicate rich running but the O2 sensor should compensate or the ECU will complain, maybe there is an exhaust air leak or leaky injectors.

[Jimsiss]

I’m getting about 200-220 miles to £50 with a 16T full 3” exhaust and MBC, that’s mostly short journeys of around 10-15 mins back and to to work a few miles away.

[Laird Scooby]

Originally Posted by TonyS9

Its a bit lazy not working out the mpg and expecting us to guess!

80mph is gonna give you about 24mpg in my experience. That should translate to £50 @ £5/gal for your 240mile trip, so yes seems excessive at 3 times. You are talking single figure mpg.

Smelling of fuel could indicate rich running but the O2 sensor should compensate or the ECU will complain, maybe there is an exhaust air leak or leaky injectors.

£5/gallon????? I want the address of your filling station! Round here it's about 135p/L which is about £6.60/gallon (Super Unleaded @ Sainsburys, normal station and normal unleaded about the same price) but the OP using £150 to do a 240 mile trip?

On a rough approximation, £50 is just over 8 gllons so £150 would be just over 24 gallons - that equates to 10mpg!

Given the other symptoms of rough idle etc, i'd look at the cat, sounds like it's blocked.

Originally Posted by Jimsiss

I’m getting about 200-220 miles to £50 with a 16T full 3” exhaust and MBC, that’s mostly short journeys of around 10-15 mins back and to to work a few miles away.

That's about 8 gallons so 25-27mpg roughly - considering your journeys that's about right.

[360beast]

In my 940 automatic I just did a run of 212 miles and then town driving taking the total up to 266 miles and that used £50 which equates to 30mpg

Bloomin neck Dave! Sainsbury's here is £1.24 a litre!

[Laird Scooby]

Originally Posted by 360beast

In my 940 automatic I just did a run of 212 miles and then town driving taking the total up to 266 miles and that used £50 which equates to 30mpg

Bloomin neck Dave! Sainsbury's here is £1.24 a litre!

That's about 34mpg Luke, not bad at all.

Is that for normal unleaded Luke? It was 124p/L for Super until recently and jumped about 10p/L in a fortnight!

[Clan]

Originally Posted by deeman940

i would like some opinions please,,,,
i always thought that my 940 was very good on fuel considering it's age and size, but have never really taken it on a long run to determine this.
It was recently in the garage for a year (long story) and had only been started up and moved outside then started and moved in at the end of the day.
when i got it back it was very 'grumpy'...stuttering and wouldn't idle etc (to be expected), Shortly after i took it on a run to Plymouth (240 miles) in which it used the best part of £150 in fuel including driving around down there a bit but not much at all. i thought this was a bit excessive but figured the plugs were coked up after a year of not being run, coupled with smelling slightly rich,
i then changed the plugs to see if this would improve things, i did another run to Plymouth and it fared very slightly better but not a great deal.
i did a run to Birmingham tonight (100 miles) and used £30 each way so roughly the same as the Plymouth run, Since Plymouth the car has had new dizzy cap, rotor arm and HT leads,oil and filter and fuel filter change
does this seem excessive to anyone? i was not using a heavy throttle (80 mph average) and the car has a MBC, air filter and 3" exhaust,
It also seems to bog down in first alot ( running rich??)
Anyone have any ideas?
it could of course all be my imagination and this is the sort of consumption to be expected?!
Damo

80 average !! that means you are doing over 90 mph that uses about two or three times as much fuel as doing 60 mph , just slow down :-)

[john.wigley]

For many years 'LS', I have maintained a simple spreadsheet from which I know that (with approximately half a tank of fuel remaining) I have put 1686.97 litres of petrol into my V70 at a cost of precisely £2000, over three years and 10,841 miles. From that I compute my MPG, MPL, PPM and any other statistics that I require.

Using the same method, my late lamented 2.3 745 consumed 10,442.82 litres of fuel in travelling 62,746 miles, which equates to 27.3148 MPG, or 21.6 PPM (adjusted for present day fuel cost). Compared to that, Damo's 940 does indeed appear to be much too 'juicy'.

Regards, John.

[Laird Scooby]

Originally Posted by Clan

80 average !! that means you are doing over 90 mph that uses about two or three times as much fuel as doing 60 mph , just slow down :-)

I suspect what he really means is on the dual carriageways/motorways he was driving, for the most part, at about 80mph which isn't 80mph average speed.

Had to explain to a friend recently that although she claimed to have averaged 70-80mph on a journey, her actual average speed (distance/time) was in fact about 43mph and the only reason round these parts it was above 40mph is because she had half of the journey on a fast A road and 1/4 of the journey on dual carriageway.

It's a common misconception that the speed the needle indicates for the most part of the journey is the average, so many things can knock a big hole in the true average speed such as stopping at motorway services for a "comfort break", caught in roadworks doing 30mph in the contraflow and so on.

To achieve 80mph average speed on a 240 mile journey, it would only take 3 hours and the speed for most of the journey would have to be in the region of 100-110mph to counteract the town driving and so on.

[deeman940]

I suspect what he really means is on the dual carriageways/motorways he was driving, for the most part, at about 80mph which isn't 80mph average speed.


That's what i meant Dave, thanks for clarifying, right so it does appear to be guzzling!
The car has been de catted so that is not an issue!!
Could it be a clogged AMM? (suspected) or a dirty throttle body? (suspected)
The Lambda/ emissions light came on on the first trip to Plymouth, is this a clue?