hdi economy

Discuss, ask, or get help with engine and mechanical queries in here.

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darrenwall
2.0 Turbo
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Post by darrenwall »

im getting between 42 to 45 mpg out of my d8 2.1 td estate so i dont think thats bad considering its just past 200k miles , its got no exhaust from the cat back :shock: and i drive it like i stole it lol most of my mileage is dual carriageway so i usually do about 85 ish ( only on private stretches of road mind :cheesy: ), thats loads better than my old 405 mi16 tho , if i took my time i would get about 25 mpg but when i used to drive it properly it would go down to about 12 mpg :shock:
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neildavies
3.0 24v
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Post by neildavies »

jameslxdt wrote:
neildavies wrote:shich I did to tkae the photo
and what language is this? :P
I have no excuse other than not proof reading my typing! Can't even blame it on drink at that time of day!
darrenwall wrote:thats loads better than my old 405 mi16 tho , when i used to drive it properly it would go down to about 12 mpg :shock:
F**king OUCH!!!
2007 Mondeo Titanium X 2.0 TDCi
2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi
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darrenwall
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Post by darrenwall »

neildavies wrote:
darrenwall wrote:thats loads better than my old 405 mi16 tho , when i used to drive it properly it would go down to about 12 mpg :shock:
F**king OUCH!!!
when i mean drive it properly , thats 7500 rpm in ALL gears :cheesy: , thats the only way to drive it tho lol
scrapheap
1.8 8v
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Post by scrapheap »

Acceleration is your friend - the sooner you peg it up to 56 - 60mph the better - that means you'll be spending the most distance at the most economical speed.

Brakes are your enemy - these convert the fuel you have just burned to get to that speed into heat and dust that do nothing useful for economy.

Coasting is your enemy - on downhills, keep the car in gear, just take your foot off all the pedals, DO NOT put the car in neutral - you're using fuel to keep the engine going, rather than using the momentum of the car.

Momentum is your friend - it's more economical to accelerate down the hill, than to accelerate up the other side - if you can, build up speed on the downhill slopes ( gravity giving you that extra pull ), and cruise up the hills only using the accelerator if you're going to stop or get to such a slow speed you're dangerous.

Accelerating around bends is your enemy - a percentage of the power the engine is generating ( and fuel used ) goes in friction on bends, and if you understeer, you'd be using fuel to do that !

Long waits at traffic lights are your enemy - turn the engine off as long as it's warm.

Stop-start traffic jams are your enemy - stick it in 1st, leave a gap and try and keep moving as long as possible without using the breaks, at least you're still gettign SOME mpg rather than NO mpg when stopped !

When we had th fuel crisis ages ago, I managed to boost my economy from around 45mpg to over 65mpg just by thinking about what I was doing, and that was in a 1.7 common rail 90hp car.

Anyway, back to work in the server room ( yes, another IT bod :cheesy: )
2.1TD LX Cat C
No longer in use, and SORNED due to..
Steering leaking.
Back door stuck shut.
MOT and Tax out.
Baby on the way, so now have a 405 Estate
Any offers for the 406 ?
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Captain Jack
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Post by Captain Jack »

Weekend mornings in server rooms... ah the memories... :D
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Welly
The moderator formally known as Welton
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Post by Welly »

scrapheap wrote: Coasting is your enemy - on downhills, keep the car in gear, just take your foot off all the pedals, DO NOT put the car in neutral - you're using fuel to keep the engine going, rather than using the momentum of the car
I agree with you, BUT there is a problem here with the build up of heat. Fuel is the only in-cylinder coolant available, without it you will be using your engine as a compressed air machine getting the piston crowns very hot, a bit nerdy I know but hey.
Cars in my care:
2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
2013 Renner Twingo - donkey work
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mjb
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Post by mjb »

scrapheap wrote:Acceleration is your friend - the sooner you peg it up to 56 - 60mph the better - that means you'll be spending the most distance at the most economical speed.
Wrong. My car will return well under 10mpg over the hundred yards or so (? - never worked that out) it takes me to do 0-60 quickly. If you accelerate slowly taking twice the time at say 30mpg, you're using much, much less fuel.

At the end of a 60 mile journey with the average counter showing 42mpg, I can floor a 0-60 and just that alone will drop me an average of 2mpg!

Coasting is your enemy - on downhills, keep the car in gear, just take your foot off all the pedals, DO NOT put the car in neutral - you're using fuel to keep the engine going, rather than using the momentum of the car.
Not necessarily, it depends if the hill is steep enough for you to maintain speed without having to use the accelerator. There's a 3 mile stretch on the A500 southbound between the A34 and A527 which can be coasted to give a steady 60mph if not slipstreaming - in which case you accelerate. That stretch of road gets me somewhere in excess of 100mpg (damn trip computer only goes to 99.9) when coasting but only around 65mpg when in gear

Momentum is your friend - it's more economical to accelerate down the hill, than to accelerate up the other side - if you can, build up speed on the downhill slopes ( gravity giving you that extra pull ), and cruise up the hills only using the accelerator if you're going to stop or get to such a slow speed you're dangerous.
Yes, but on a busy motorway not keeping a steady speed for no good reason makes you an arsehole. However when I'm loaded up with passengers that's what I do :)
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neildavies
3.0 24v
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Post by neildavies »

darrenwall wrote:
neildavies wrote:
darrenwall wrote:thats loads better than my old 405 mi16 tho , when i used to drive it properly it would go down to about 12 mpg :shock:
F**king OUCH!!!
when i mean drive it properly , thats 7500 rpm in ALL gears :cheesy: , thats the only way to drive it tho lol
Yeh, I knew you meant it that way. To be fair, you've got to drive an MI16 like that now and again. Wouldn't have been worth having it otherwise.
2007 Mondeo Titanium X 2.0 TDCi
2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi
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406 express
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Location: The Wirral

Post by 406 express »

done my rear discs, pads and shoes today changed the oil and filter as well, what a difference! completely different car, lot smoother and responsive, better economy as well, in to the high 40s
if you don't know where your going, any road will take you there
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mjb
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Post by mjb »

Amazing the difference freely turning rear wheels can make, eh? :)
mbell666
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Post by mbell666 »

mjb wrote:Amazing the difference freely turning rear wheels can make, eh? :)
Finally got round to fixing my rubbing rear brake (rear pain of a job), in the 5 miles i've driven you can free the difference. Hopefully will notice the difference on the next tank full (fingers crossed to be back to the right side of 50mpg).
1997 Honda Prelude 2.2 VTi
Previously - 1999 406 Executive HDI
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