Diminishing mpg

tipptom

I bought a 04 volvo 2.5 v70 awd 7 seater auto petrol(no sniggering down the back)about 5 months ago.
At the time it was showing 29.2mpg on the clock.It has worked its way slowly but surely back to 24.8 at the moment.
Done the oil,oil filter,fuel filter,air filter and plugs all to no avail for my slowly diminishing returns.Also find that when it is idling in park or neutrel it is up and down a bit when left for a few minutes.
Anyone any ideas on what the next move should be in the most inexpensive way?

R.O.R

tipptom wrote: »

I bought a 04 volvo 2.5 v70 awd 7 seater auto petrol(no sniggering down the back)about 5 months ago.
At the time it was showing 29.2mpg on the clock.It has worked its way slowly but surely back to 24.8 at the moment.
Done the oil,oil filter,fuel filter,air filter and plugs all to no avail for my slowly diminishing returns.Also find that when it is idling in park or neutrel it is up and down a bit when left for a few minutes.
Anyone any ideas on what the next move should be in the most inexpensive way?

Was the 29.2mpg from the previous driver, and your driving has brought it down to 24.8? If so, the type of driving they were doing could be a lot different from yours - possible they were doing mainly long runs and you are around town more?

Can't help on the technical question I'm afraid, but nice motor and by god you are either very brave to take one of those on, or you got it for a steal.

Black_Knight

doesn't the cold affect mpg? Winter could be your answer.
I've noticed a slight drop in my own car too. Granted I've only had it since October, and its diesel not petrol.

Engine takes longer to heat up to optimum temperature, greater on in the car to warm those chilled bones. Think the cold does something to the actual fuel itself too.

tipptom

R.O.R wrote: »

Was the 29.2mpg from the previous driver, and your driving has brought it down to 24.8? If so, the type of driving they were doing could be a lot different from yours - possible they were doing mainly long runs and you are around town more?

Can't help on the technical question I'm afraid, but nice motor and by god you are either very brave to take one of those on, or you got it for a steal.

I dont think so,i am out the country,bought it from the city.
Bought it fairly right ok with 6 months tax,time to pay the piper now though,tax is horrific any money saved will soon be eaten up by the road tax man.

corkgsxr

Could be worth going to a independent garage and put diagnostics on it. An show up interesting results

RidleyRider

Just did a quick search on google, maybe you could try this; http://www.motormods.co.uk/econo_tune.html

Effectiveness? I don't know but maybe someone here has done it and can tell you more.

DanWall

Are you loading lots of bits and bobs and tools in your boot, Also check under the wheel arches, are they thick of mud, the weight can decrease you mpg

Ninap

I've got a 04 2.9 XC90 and around town I'm getting an appalling 16mpg (according to the obc). The previous owner of your car could have just reset the computer and gone for a few runs at very slow speeds / low revs to produce a good mpg reading....

jayok

Ninap wrote: »

I've got a 04 2.9 XC90 and around town I'm getting an appalling 16mpg (according to the obc). The previous owner of your car could have just reset the computer and gone for a few runs at very slow speeds / low revs to produce a good mpg reading....

16mpg!! I nearly bought one of them...

jthrppel

Is this diesel or petrol? We had a petrol 00 2.0T and the best Dublin
urban mileage we were getting was around 23-26 mpg. First, reset/clear computer and take it on a long motorway ride and see what mpg you get. If the idling is rough (ie. not steady at about 900-950 rpm), you may want to get it tuned. Does the engine heat up to operating temperature (needle in the middle of the dial if it is like my 00) within 5 minutes or so after starting? We had once that engine temp sensor gone bad and that could give wrong inputs to the computer. Tire pressure and thread level would be another thing to consider. Also it might be worth considering the driving style, such full throttle take off vs slow to get to 3rd, pulsing throttle vs. continuous. Around 00 reg, there was a problem with Electronic Throttle Control? system of the V70 and it will loose power at high speeds and go into limp mode. I do not know whether that had any effect on mpg, likely not.
james

MagicRon

Could it be the fuel you are putting in it? I know of a few service stations back home where I'd never get the distance from a tank that I'd get filling elsewhere. Easy one to rule out, don't fill at the same shop

RidleyRider

MagicRon wrote: »

Could it be the fuel you are putting in it? I know of a few service stations back home where I'd never get the distance from a tank that I'd get filling elsewhere. Easy one to rule out, don't fill at the same shop

I'd agree with that. Was one of those cheap fuel places in town not so long ago and I started filling the car with petrol there thinking 'oh great, cheap fuel'. Little did I know, the car was drinking the fuel down! Was putting 90e or so into a 1.1 for 800km driving a week? Nuts.

Fill at a local Topaz now and the bill has dropped about 25-30 euro.

Ninap

jayok wrote: »

16mpg!! I nearly bought one of them...

Yeah, it's shocking, and the tax is 1400 plus now. But it's comfortable, fits the kids plus bike and stuff, and I've just had the alloys refurbed so it looks nice too

C.K Dexter Haven

All car displays/computers showing mpg can be easily manipulated during time of sale to show more favourable mpg OP, by simply resetting it usually by a switch or button in the car, then driving it very carefully.
In addition, driving behaviour can make a difference of a few miles per gallon easily- with this in mind, there's nothing extraordinary about your claims.
Max mpg claimed I think is around 31. 26/27 is not far off that and if you do a lot of short journeys or town traffic, then it's fairly normal I'm afraid.

Wicklowandy

Id never believe a trip meter until id verified it.

Fill the car. Note the litres and price of fuel. Drive a set distance, say 200 km.

Fill again. Now you know how much fuel takes you 200km. Work out your l/100km or mpg from that.

Do that before any diagnostics or anything else;)

alexlyons

1.4 petrol focus and ive noticed it drop 1l/100km in the last two fills. really dreadful fuel economy, worse than these yolks are known for. it's killing me, id prefer to have something nice with this bad fuel economy, say a 320i E90...

Dardania

This is the spritmonitor page for your year of car: http://www.spritmonitor.de/en/overview/51-Volvo/468-V70.html?fueltype=2&constyear_s=2004&constyear_e=2004&power_s=200&power_e=210&powerunit=3

The average consumption for petrols is: 10,51l/100km = ~ 26.87736MPG , so it looks as though you're slightly, 7% below average.

Check your fuel supply - I find Applegreen gives me good MPG, but your mileage may vary...

tipptom

Thanks for all your reply guys,I think it looks like this is not out of the ordinary for this carmpg wise, as long as it does not keep falling.Not sure if an Indys diag would show as much as the main dealer.
I had considered biting the bullet on it and taking it in to volvo in Limerick and getting them to stick it on the diagnostics(around €100 i presume)because I sometimes find with the Indys is,"We will replace this first and see how it gets on",and when it doent work its on to something else and it becomes an expensive merry go round.

Will check out the mpg properly and and reset the computer and see how it goes.
Anyone got a solution to a €1,460 motor tax if I tax it every three months!!!:)

Wicklowandy

You dont want to go there, see thread on topic

tipptom

Wicklowandy wrote: »

You dont want to go there, see thread on topic

Oh jeez no,knew what I was getting in to in that respect when I bought it so no Im not going there:D

piston

Fuel consumption will drop at this time of year anyway as you will have the headlights, heater fan, heated back window and other electrics that you don't usually use over the summer. It will also take longer to reach it's proper operating temperature.