S80: General - Poor MPG on 2008 S80 D5 (185) Manual

sjc123456789 · Aug 1st, 2011, 19:12

Hi All, I’ve noticed quite a few posts on mpg, sorry for adding another, but I’m a little confused and thought someone might help me.

I’ve had a 2004 S80 D5 163bhp Manual for about 4 years and 50,000 miles (85,000 to 135,000) and it returned 44mpg over the whole period (from diesel receipts, the dash showed anything up to 55mpg avg.) – mixed driving, motorways and town. Over the period I had highs of about 50mpg when the driving was predominantly motorway and lows of “high 30’s” when it was mainly town driving.

The new car, is a 2008 S80 D5 (185) manual with 83,000 miles. Over the last couple of thousands miles its only done about 34mpg (same driving as old car) and it’s difficult to do more than 600 miles between fills, the old would do 700 plus with ease.

• I know the driving style is the same (I have a tracking box fitted that give normal telematics telemetry plus driving style).
• The Temperature is roughly the same (seasonal variation was minimal as I don’t idle),
• the area driven is the same,

• the tyres are different, 245/40 vs. 225/50 but both have optimum pressure for economy

• I think the weight of the car is with %

• Although I don’t know specific cd / cda I would expect it to be better on new car

So why the 10mpg drop ? that’s 22%

That can’t be down to emissions can it?

Help!!!

october37 · Aug 1st, 2011, 20:42

Your present S80 185bhp car will have a DPF fitted which makes the fuel consumption higher than the previous 163bhp model because it uses a process which Volvo Dealers term as "Diesel Up" to purge the filter of accumulated soot every so often. This process takes about 20 minutes to complete at aprox 40 mph and is designed to stop the Diesel Particulate Filter from cloging up and causing the engine to go inte Limp Mode. Your average fuel consumption for the 185 bhp engine should be iro 42+ mpg.

55reg V70se D5 AWD Geartronic

sjc123456789 · Aug 1st, 2011, 20:49

good info thanks.

how do i know if the dpf is being cleaned?

thanks Simon

apersson850 · Aug 2nd, 2011, 08:50

You don't, but you may occasionally notice that it's suddenly impossible to achieve the same consumption at constant speed as you are used to. And then suddenly it is, again. That's typical of the filter being cleaned.

There's also often differences between one identical vehicle to another.

Don't know for sure about the S80, but at least the V70 of the latest incarnation has more air resistance than the previous one had. Appearance rules over technology.

sjc123456789 · Aug 2nd, 2011, 10:21

thanks for that.

you're probably right, style over ..... aero.

Aug 1st, 2011, 19:12	#1
sjc123456789 Junior Member Last Online: May 22nd, 2023 12:42 Join Date: Apr 2006 Location: Pontefract	Poor MPG on 2008 S80 D5 (185) Manual Hi All, I’ve noticed quite a few posts on mpg, sorry for adding another, but I’m a little confused and thought someone might help me. I’ve had a 2004 S80 D5 163bhp Manual for about 4 years and 50,000 miles (85,000 to 135,000) and it returned 44mpg over the whole period (from diesel receipts, the dash showed anything up to 55mpg avg.) – mixed driving, motorways and town. Over the period I had highs of about 50mpg when the driving was predominantly motorway and lows of “high 30’s” when it was mainly town driving. The new car, is a 2008 S80 D5 (185) manual with 83,000 miles. Over the last couple of thousands miles its only done about 34mpg (same driving as old car) and it’s difficult to do more than 600 miles between fills, the old would do 700 plus with ease. • I know the driving style is the same (I have a tracking box fitted that give normal telematics telemetry plus driving style). • The Temperature is roughly the same (seasonal variation was minimal as I don’t idle), • the area driven is the same, • the tyres are different, 245/40 vs. 225/50 but both have optimum pressure for economy • I think the weight of the car is with % • Although I don’t know specific cd / cda I would expect it to be better on new car So why the 10mpg drop ? that’s 22% That can’t be down to emissions can it? Help!!! Last edited by sjc123456789; Aug 1st, 2011 at 19:44.

Aug 1st, 2011, 20:42	#2
october37 Senior Member Last Online: Mar 17th, 2023 13:24 Join Date: Nov 2001 Location: Whitehaven	Your present S80 185bhp car will have a DPF fitted which makes the fuel consumption higher than the previous 163bhp model because it uses a process which Volvo Dealers term as "Diesel Up" to purge the filter of accumulated soot every so often. This process takes about 20 minutes to complete at aprox 40 mph and is designed to stop the Diesel Particulate Filter from cloging up and causing the engine to go inte Limp Mode. Your average fuel consumption for the 185 bhp engine should be iro 42+ mpg. 55reg V70se D5 AWD Geartronic

Aug 1st, 2011, 20:49	#3
sjc123456789 Junior Member Last Online: May 22nd, 2023 12:42 Join Date: Apr 2006 Location: Pontefract	good info thanks. how do i know if the dpf is being cleaned? thanks Simon

Aug 2nd, 2011, 08:50	#4
apersson850 Premier Member Last Online: Today 13:07 Join Date: Jul 2011 Location: Traryd View Photos By: apersson850	You don't, but you may occasionally notice that it's suddenly impossible to achieve the same consumption at constant speed as you are used to. And then suddenly it is, again. That's typical of the filter being cleaned. There's also often differences between one identical vehicle to another. Don't know for sure about the S80, but at least the V70 of the latest incarnation has more air resistance than the previous one had. Appearance rules over technology.

Aug 2nd, 2011, 10:21	#5
sjc123456789 Junior Member Last Online: May 22nd, 2023 12:42 Join Date: Apr 2006 Location: Pontefract	thanks for that. you're probably right, style over ..... aero.

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