Hello...new member - Clio dci

[Smithsk71]

Hi all.

Been having a good look around the site and forum getting some ideas

Just clocked up the first 10,000 miles in my last of the line Clio mkiii DCI bought back in February. Been reading some dpf horror stories on the web but with the miles I'm doing and the type of roads/driving I don't expect any issues (famous last words).

Have not seen below 60mpg over a tank of fuel so far but sometimes I lament my mkii DCI which was well into the 70s being that much lighter...however the new car has got more creature comforts

Going to try some tips from here to aim for 70 plus.

Once the kids are off school for xmas I'm going to swop with the wife temporarily and use the family bus / 2008 VW Touran tdi mainly used on shorter journeys - thankfully it's pre-dpf! It needs a good clear out but I think 60 should be possible.

Anyway that's enough rambling...good info on the site, thank-you.

Steve.

[frv]

Hi Steve and welcome to the forum.
I'm sure we can help!

[Smithsk71]

Thanks FRV.

So, getting started...

First thought I would see how accurate the speedo/odo is. Since it's a built-in sat nav it doesn't show speed (don't want to show their speedo to be inaccurate I guess)...so I got my old sat nav alongside. Both sat navs showed the route to work to be 25.7 miles. I reset the trip counter and by the end of the journey it too had recorded 25.7 miles. Speedo was about a 1-1.5 mph out, usually cruise at 55mph and they were reading about 53-54. Google maps also shows the route to be 25.7

So that seems a good place to start to me - having a reasonably accurate odo, then I can just brim the tank and Fuelly can work out the mpg. I've tended to use Shell garages and there is one just after I leave for work and one about halfway back so I don't think brimming will be an issue - especially since it's a diesel. I suppose the first time I fill it to the brim (next time) will make the previous tank's economy look rubbish but gotta start somewhere.

I don't have an instant mpg readout on the trip computer so will have to make sure that I record the odo at fills so I can get reset the mpg each day. By the time I got to work this morning it was showing 75mpg but I'd reset it after I was moving...doh!

Only techniques I am using at the moment are coasting in gear, trying not to use the brakes and drafting if there happens to be something suitable.

[frv]

What you are doing is a great start.

All speedos will read low to actual speed, never higher. My speedo reads about 3mph low at 60mph indicated.
From VW:
"To allow for possible differences in overall tire diameter with different tire manufacturers and wheel sizes, a factor is designed into the speedometer function that increases the displayed speed. This factor does not affect odometer readings, which show actual distance traveled."

The last statement isn't actually true as I've found most odometers read less miles than actually covered and there's also got to be a small difference as your tyres wear.

We've had a discussion about sat-nav accuracy previously (which hurt my head ) here: http://www.hypermiler.co.uk/forum/viewt ... f=14&t=886 but it sounds like yours is pretty accurate.

My car doesn't have instant mpg readout either that's why I bought an UltraGauge (thread here: http://www.hypermiler.co.uk/forum/viewt ... ultragauge ).
Resetting the trip mpg will help you gauge if what you are doing is helping to a degree just take the numbers with a pinch of salt, they generally read high! Doing a brim to brim tank will give you much more accurate numbers.

You say you are coasting in gear - are you doing any coasting in 'N'? Unless you are going down a steep hill, coasting in 'N' will normally get better fuel economy. Again, some great discussion have taken place on this subject http://www.hypermiler.co.uk/forum/viewt ... f=17&t=598.

Check your tyre pressures. You can put them up a lot more than you think:
http://www.hypermiler.co.uk/forum/viewt ... f=17&t=498

Finally speed has to be this biggest factor. I have seen many graphs of the fuel economy of different cars at increasing speeds and the main conclusion is speed kills FE! You should be aiming to go as slow as you can get away with - On a motorway 50 to 55 would be good if you stick with the lorries plus you get the added advantage of drafting which you mentioned - just keep a safe distance.

According to the Department for Transport, driving at 70mph uses up to 9% more fuel than at 60mph and up to 15% more than at 50mph. 80mph can use up to 25% more than at 70mph.

Found this as an example on the net:

mpg at mph.jpg (33.69 KiB) Viewed 20232 times

and this one is an old one from Wiki but it's the same principle:

Fuel_economy_vs_speed_1997.png (31.26 KiB) Viewed 20232 times

[tighterse]

Hello.

I don't give advice - I simply comment. Then I can never be accused of misleading.

Firstly, I don't believe in brimming. All your doing is carting around surplus weight and lending the oil companies money - interest free. I only buy as much as I estimate I'll need for the next week. I don't know Bedfordshire but I'm sure there's no shortage of petrol station.

Secondly, Fuelly. I do use it but only to make my records reasonably public. A notebook or a spreadsheet will do just as well and, with the latter, you can produce lots of lovely graphs comparing you mpg with miles covered and time. Some folk I hear also record weather conditions.

Thidly, drafting. If there is a following wind I feel it is better to take advantage of that. Drafting is very useful in still air conditions or into a headwind. It does take a great deal of concentration and I have found that using supermarket lorries or Stobart's lorries to be the most reliable; they tend to operate at steady speeds and also use cruise control.

Fourthly, speed. On a motorway I tend to set the cruise control at an indicated 60 to 65 and, rather than the accelerator, use the CC
to control my speed. However, on "A" roads I stick to around an indicated 50/55 and find that is considerably more economical.

Fifthly and finally, coasting. I don't think there's much doubt that coasting in neutral is best and keep the clutch depressed to help reduce mechanical drag.

Best of luck and orrabest for the festive season.

[Smithsk71]

Thanks, all good info and seasons greetings to you too!

We once had a new Golf Estate TDI and the economy was amazing but it was scary as hell and we couldn't work out why...needless to say the tyres were wayyyy over-inflated straight from the factory I'm probably over by only a psi or two just now. It's a boring straight run though and the tyres were coming up to 30k when I parted with the old clio!

I want to brim it at first just to find out how far it is possible to go on a whole tank and see how far off the computer's mpg estimate is.

Bedfordshire is pretty darn flat, maybe that explains the satnavs accuracy somewhat Will have to work out where to test neutral coasting.

With regard to the Ultragauge I'll see how the Torque Android App with bluetooth obd reader goes - hopefully I can find the sweet-spot and drive accordingly. I'm a total gadget/stat freak - should have 2000 miles of cycling gps logged by the end of the year! Hope to do more cycle-commuting next year in the spring.

Until I get some known accurate mpg I won't post anything in the stats.

Today I had a rare trip just to the station to commute to London instead, had to scrape the windscreen too after I reversed up to the garage (think it's better to only do that in the spring/summer/autumn! )
52.3 / 9.9mi - back to a proper run tomorrow...the car never properly warmed up tonight @ 6c - that would be a DPF killer for sure if I was doing it everyday.

[Smithsk71]

Yesterday 66.7 / 54.9mi
Today 68.5 / 63.8mi (oil and filter changed). Both very cold days 1c-6c.

Still going to be a while before I can brim and work out how accurate (or not) the trip computer mpg is.

[frv]

You've almost got your 70 target and it's been cold, excellent work

[Smithsk71]

68.6 / 51mi today, these are always 1up.

Got a 160 mile round trip to Kent tomorrow with 4up but not going to let the family mess up my efforts in the Clio so will let them enjoy the space of the family car. Aiming for something north of 50.

Windscreen smartphone holder arrived today but sadly not the Bluetooth obd2 reader...have to wait a bit longer to have a play

[Smithsk71]

Was only 2up in the end so took Clio after all. Couldn't hold 70mpg on the way due to traffic at the end but nailed it on the way back despite the A1 being closed around the Hatfield tunnel That stretch of the A1 is constantly up and down...got the knack of faster downhill and slowing gradually on the uphills to good effect.

70.3 / 170.1mi - not sure what the temperature was.

Going to need to fill up Tues or Weds, might do a whole tank with these techniques before adding any air to the tyres.