Poor MPG

Forum for Engine, Exhaust, Drivetrain, ECU
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Fee
Posts: 2057
Joined: Thu Dec 22, 2011 6:08 pm

Poor MPG

Post by Fee » Mon Mar 02, 2015 7:34 pm

My dci doesn't do well MPG wise in the winter and has been known To go to late 30's... My first DCi regularly hit 32 MPG.

I am pleased to say my current dci is doing late 40's short urban stop/start journeys and early - mid 60's on my 200 mile round trip each month,,,

I am pleased with my MPG, I just wish the fuel tank was bigger though,,
1.5dci Tekna Gunmetal/Red - June 2015
1.5dci Ntec in White - 2013
1.5dci Acenta Premium in white 2010


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Jukes
Posts: 48
Joined: Fri Feb 27, 2015 5:56 pm

Poor MPG

Post by Jukes » Tue Mar 03, 2015 2:03 pm

Hi Tom,Your daily millage is very low as already pointed out. I also have the diesel and do low millage myself in fact I cycle to work instead. Its a known fact that diesels dont enjoy short trips and that a longish stint is necessary to keep it top shape. I enjoy my drives on weekends and this usually involves a good hour each way on the motorway, this the diesel LOVES and it clears its throat from any urban use clogging.My Juke is only a new buy but I've driven diesels for years and I'm a qualified mechanic. I used to work in Nissan and BMW dealer for years. I like to chuck in a fuel additive in the way of injector cleaner every 30k or so.. just to keep things in top shape, its not expensive so give it try on an empty tank while your at the pumps just before you fill it up, this will mix and dilute the additive like a glass of Robinsons . As pointed out it takes a bit of time to warm the diesel so it will naturally be idled a bit higher by the ecu which does what the old fashioned choke used to do and its also winter so that will take even a bit more. In urban use there's actually not much difference between a petrol and diesel in terms of mpg, both are at their worst and it suits a normally aspirated petrol engine much more than a turbo diesel. You will notice truck and large commercial divers prefer to let their engines idle rather than switch it off and start again even if they're just hanging around for a long time. This is because engines are at their best tolerances with piston rings, cams, oil viscosity's be it engine, gearbox and so on.. when at optimum temperatures and these drivers want to keep it that way to protect against wear and damage. If your doing small millage I would definitely recommend a petrol which just suits that urban stop start, cold hot cold etc better than I diesel, a petrol doesn't like that either but it just suits it better Other than that I would check simple service items that might restrict performance such as the state of air filter and the fuel filter.. not much else really.. faults in heater plugs and other more expensive issues would be evident in how its slow to start or loss of power or shuddering etc or show up as a fault. Just one word of warning however.. short trips where the engine doesn't get a proper chance to heat can also kill a turbo which is very very pricey in labor... so the best way to look after your turbo, especially winter, is to start your engine up and wait for a minute before driving, literally a minute. This will allow the oil which will be cold and at its thickest and slowest to move in and around the turbo bearing and so it will get well lubricated and ready to spin and an insane rmp as turbos will and do.. just imagine spinning that turbo at thousands of revs when its its cold which as what most people will do as we all have to rush to work or something and with oil and temps not where it needs to be at.. its just going to shear and wear that bearing each and every time resulting in a dead turbo eventually


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MikeGC
Posts: 700
Joined: Sat Jul 19, 2014 12:17 am
Location: Stockport

Poor MPG

Post by MikeGC » Tue Mar 03, 2015 4:16 pm

I always leave my diesel turbo ticking over for a minute when I stop for the same reason
This was advice given to me with my first turbo diesel purchase, 20 years ago
MikeGC
1.5dci gunmetal grey ascenta premium with red exterior/interior packs


moncrieffey
Posts: 156
Joined: Thu Feb 19, 2015 8:50 am

Poor MPG

Post by moncrieffey » Tue Mar 03, 2015 4:19 pm

So would you's advise on the diesel, on start up to let it idle for a minute and same when you stop?


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MikeGC
Posts: 700
Joined: Sat Jul 19, 2014 12:17 am
Location: Stockport

Poor MPG

Post by MikeGC » Tue Mar 03, 2015 4:45 pm

I've never heard the start up procedure before.I suppose if you drive straight onto a fast A road, it would make sense.Additionally it takes me about 3 minutes to get to a bit of road where the turbo might start working, as I drive at low speed (kids, parked cars, etc.)My pre-switch off routine just keeps the oil circulating and cooling the turbo for that extra minute to protect it as far as possible.
MikeGC
1.5dci gunmetal grey ascenta premium with red exterior/interior packs


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Dominic
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Joined: Wed Oct 08, 2014 9:43 pm

Poor MPG

Post by Dominic » Mon Apr 06, 2015 9:18 pm

Thanks Jukes for that really informative and easily understood run down on engines and choices.... I'm downsizing from my QQ to a Juke in the next few weeks. And I'm so uncertain about sticking with 1.5 diesel, or trying out the 1.2 DiG-t petrol. Currently I'm averaging 622 pcm miles. Just under 10,000pa. And whilst either engine would be fine, as ocassionly (1 /2 month) I do a motorway trip..... I need to not be tempted by the 'so called' official economy of the diesel. Having driving both today again, the petrol is very nippy and chuckable! A fund drive.... And suits me more, as 90% of my daily driving it busy town stop/start and occasional open A roads. And only me in the car so no need for lots of low down pulling power torque..... Plus the 1.2 is incredibly quite! My QQ 1.5 often sounds like a tractor! Now all i've left to decide is trim level...... Tekna or AcPrem. Not keen on leather interior, but I like all the extra technology you get in the Tekna. The easy part was colours. Already have that all picked out! lol.Anyway, thanks again, for the informative earlier post Dom.


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actd
Posts: 2251
Joined: Wed Aug 01, 2012 11:18 am

Poor MPG

Post by actd » Mon Apr 06, 2015 9:39 pm

If you go for the 1.6 DiG-T acenta premium, you get the fabric seats but also the folding mirrors and auto lights and wipers, I believe. Not on the 1.2 though.
2012 - Acenta Premium dCI - Gun metallic
2014 - Acenta Premium 1.2 DiG-T - Nightshade
2015 - Acenta Premium 1.6 DiG-T - Black
2017 - N-Connecta 1.6 DiG-T - Black


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Lukeplayer187
Posts: 283
Joined: Thu Oct 02, 2014 6:28 pm

Poor MPG

Post by Lukeplayer187 » Mon Apr 06, 2015 9:44 pm

You can get all the same tech as the TEKNA on the accenta premium, you just have to pay the extra for upgrades. So you get all the gadgets appart from the heated seats with out the leather which is the way I ordered my car. Oh and you don't get the dodgy keyless entry with button start which in my opinion is a bonus...
Ink Blue... you know it makes sense!!!


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Dominic
Posts: 9
Joined: Wed Oct 08, 2014 9:43 pm

Poor MPG

Post by Dominic » Mon Apr 06, 2015 9:51 pm

Yeah today, the Sales guy said you can get a technology pack for the AcPrem, so basically you're getting a Tekna but minus the leather seats. But he said you have to wait considerably longer for it. Any truth in this guys? I"ve seen two brochures for the Juke, and they are somewhat conflicting to say the least. So i'm going by the website.... I guess that's the most updated information.Dom.


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actd
Posts: 2251
Joined: Wed Aug 01, 2012 11:18 am

Poor MPG

Post by actd » Mon Apr 06, 2015 9:53 pm

Damn - didn't realise that. Would have like folding mirrors. Shame you can't downgrade the connect.
2012 - Acenta Premium dCI - Gun metallic
2014 - Acenta Premium 1.2 DiG-T - Nightshade
2015 - Acenta Premium 1.6 DiG-T - Black
2017 - N-Connecta 1.6 DiG-T - Black


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