Jump to content
Do Not Sell My Personal Information


Iq Mpg On Bp Ultimate Unleaded


bobkneale
 Share

Recommended Posts

Just FYI:

Approx 1,000+ Miles covered since ownership, (Over last 3 months) 1.0ltr Manual year 2010 IQ with approx 35,000 miles on clock, I'm now sitting at a constant average of 60+MPG with short runs of no longer than 15 Miles each one, most runs are somewhat less i.e. 7-10 miles or so.

The last 3 months has been quite cold weather also, driving mostly to the speed limits of about 30-60 MPH mostly with one passenger, using cheapest petrol grade, I do tend to coast in netural gear whenever I can see far enough ahead to do so, and downhills etc,,

I cannot see much opportunity to improve on this result however, I can now potentialy foresee that a 70+ MPG will be possible on longer runs in warmer weather.

I am quite happy with this result.

Positive Regards,

Bob.

Link to comment
Share on other sites

I average 68mpg 95% motorway driving with just me in the car and traveling at 60mph.

I do know that modern engines will not use any fuel at all if you keep the car in gear and roll without your foot on the accelerator, if you coast in nuetral then the car will still use some fuel because the engine is still ticking over

Link to comment
Share on other sites

I average 68mpg 95% motorway driving with just me in the car and traveling at 60mph.

I do know that modern engines will not use any fuel at all if you keep the car in gear and roll without your foot on the accelerator, if you coast in nuetral then the car will still use some fuel because the engine is still ticking over

Hi Heathie, Many Thanks for the tip i will give the staying in gear a try ! Positive Regards Bob.

Link to comment
Share on other sites

I never see MPG like this, but then almost all my flying, sorry driving is around inner London/city, so plenty of stop/start crawling traffic. Average I'm seeing is mid to high 30's.

Maybe my lead foot doesn't help much either. ;)

Fish

Link to comment
Share on other sites

Try adding ZX1 Oil Lube? eBay is cheapest.

Link to comment
Share on other sites


I do know that modern engines will not use any fuel at all if you keep the car in gear and roll without your foot on the accelerator, if you coast in nuetral then the car will still use some fuel because the engine is still ticking over.

More explanation required Heathie!

If the engine is running at all it will use fuel, whether in gear or not, or ticking over or not.

It used to be illegal to "coast" ie put the car out of gear to run down hills etc, in the UK and I don't know if the law has changed.

It is certainly frowned upon as you are not thought to be in full control when coasting.

Some old Saabs were made with a free-wheel system but it was not allowed to be used in Britain, but of course people did use it.

John

Link to comment
Share on other sites

A modern fuel injection engine has the ability to close the fuel injectors completely so when coasting or more accurately engine braking, the injectors will be closed and although the engine is still turning over, spark plugs still sparking Etc, Not a lot happens inside the engine, it's basically now an air pump.

Once the throttle is pressed again the injectors resume letting fuel in and combustion starts again.

Coasting in neutral is pretty dangerous on many counts. No chance of accelerating quickly if you needed too, the braking ability is reduced on the servo brakes and it can increase wear on the gearbox, automatics should never be allowed to roll in neutral. That's why they say recovery of an automatic should be done with the drive wheels off the floor so they remain stationary.

Best economy I saw last year was 51mpg in the summer driving 15 miles to and from work. I do have the 1.3, 4 cylinder engine though so expect to see a bit more than those with the 1.0 engine. :)

Craig.

Link to comment
Share on other sites

Thanks Craggle, well explained.

I have never coasted in neutral as you explained above, you don't have full control of the car.

Link to comment
Share on other sites

Thanks chaps, I understand about the injectors shutting off and effectively no longer fuelling the engine but as you said Craig that is just for engine braking and you could not "coast" for any distance doing that as the car would very quickly slow down.

So that technique would not be a viable way of driving for fuel economy, or am I missing something, which wouldn't be for the first time!

John

Link to comment
Share on other sites

Take a look at Top Gear/audi a8 vb8/ fuel economy run from London to Scotland and back on one tank.

They/Jermey states at the end of the run that coasting in gear is a very/very good of way of saving fuel.

Every time I come the motorway to work I coast down the hill towards the round about, plus lots of others times and places, like I say I am averaging 68mpg

Link to comment
Share on other sites

Heathie, I really don't see how they could coast for any distance in gear with the clutch connecting the engine without the car just coming to a stop due to engine braking.

Of course you can have the car in gear with the clutch pressed and you can coast as far as you like but the engine will still use fuel as it needs to idle.As soon as you release the clutch the car will slow down and stop.

Coasting, legal or illegal, has always been a means to save fuel and the top gear chaps are correct, but you can't coast in gear with the clutch connected to the engine unless you want the car to stop, which is the way many people approach junctions etc anyway.

John

Link to comment
Share on other sites

I didn't say any thing about having the clutch engaged, that would be defeating the object.

Johnan, I think you need to try it, and yes of course you will come to a stand still eventually but you don't let that happen, plus as the engine revs drop to a certain low then you can feel the engine start up on its own, Try it, it works

Link to comment
Share on other sites

I am just not following something here and I expect it is my fault, being a prehistoric engineer trained in the 60s, though I thought I had a good grasp of modern systems, certainly mechanical ones.

I don't think my IQ2 engine works like that..It will certainly shut fuel off on the over-run but only during engine braking.

If it works for you, Heathie, keep doing it!

Let's just agree to differ and put it down to my lack of fully understanding what you have being suggesting.

Link to comment
Share on other sites


I may be wrong here, but it sounds as if you are talking about "Glide and Pulse" as a lot of Hybrid drivers do.

Or feathering the throttle very lightly.

Link to comment
Share on other sites

Way I understand it is any time the accelerator is closed, i.e. foot completely off it, the MPG goes sky high and no fuel is used. If the engine is cold that may not be true and additional load on an engine from aircon, power steering, alternator Etc may also keep a tiny amount of fuel going into the engine.

Coasting is really the wrong word for that, Coasting implies you carry on rolling along at a constant speed but with your foot off the pedal you either need to be going down a hill, have a strong wind behind you or you are slowing down. Overrun is a better word I think.

This only works on modern EFI cars by the way, A carburettor will always leak fuel into the engine and some pop and bang on overrun as evidence to this.

Craig.

Link to comment
Share on other sites

Okey dokey... here's what I do, in our manual 1.0l basic iQ. When I get the chance, coming up to a junction, lights, roundabout, and especially downhill, I do what I call coasting. By this, the car is in gear, the engine is on, I just take my foot off the accelerator and coast. Yes, unless going downhill, the car will eventually coast to a stop, which is the desired outcome -except when going downhill- to save fuel.

I find it quite satisfying that I can save a little bit of fuel at times like that. I don't go racing up to roundabouts, or junctions and slam on the brakes. My driving is -sadly- becoming more, lets say, sedate. To begin with driving at 50 in a 60 limit annoyed me, as I wanted to go faster, but I'm thinking differently with this car, almost abnormal. So, I try and save fuel everywhere I go these days in our iQ, after all, the car was bought for its frugality, so driving it like I used to drive my older cars is impossible with the tiny engine and not so great body roll at speed, or the lack of grip at speed too.

That's another thing, we now have the summer tyres back on, first time since fitting the winter tyres in October -I think it was then- 2011. Had the little plastic cap replaced with a new one that covers the fixing for the right (drivers side) wiper arm, as the other had broken clips on the inside and came off during a jet washing sesh. I put it back on, but knowing it was loose was bothering me. Aslo, had the pollen filter replaced with a new one at the same time. Last year was so bad we didn't bother changing the tyres over, so it's noticeable in the difference they work. Not as grippy, so hopefully more economical.

Went to Barmouth on Thursday, sun shiny day, great day at the beach. Fifty seven miles there, and 63.2mpg which I thought was damn good considering the hills and mountains one has to traverse to get to Barmouth from where we are in Shropshire.

By the way, I got his nice surprise from Fuelly the other day-

post-113536-0-93907100-1367661991_thumb.

Link to comment
Share on other sites

All the above is an intresting debate, I will now stop coasting in netural, and coast "in gear" and see how that improves my MPG to become greater than 60+ MPG, thanks to all for all the view and ideas knowlage expressed in the above posts.

Positive Regards,

Bob.

Link to comment
Share on other sites

  • 3 weeks later...

Just to add my tuppence worth.

In theory coasting in gear, foot off, uses no fuel as the FI systems are configured this way

In theory, coasting in neutral or with clutch in and foot off, uses fuel, as the engine uses fuel at idle. However there is lass frictional resistance in neutral,

So perhaps it evens out in the end

Healthie your ave mpg is incredible. Apart from the coasting thing, what are your secrets?

Link to comment
Share on other sites

Update on my previous posts re MPG:

Tried coasting in gear as is suggested in above posts

Tried ZX1 engine lube

Still no better MPG than about 60MPG

So I guess thats the best I am going to do unless I change to longer runs or a different route.

Positive Regards, Bob

Link to comment
Share on other sites

Mines been averaging between 28-32mpg, cry for me, I think she must be very broken

Link to comment
Share on other sites

Filled up last night and with my little andriod app, I've managed to average 50.73 out of the last tank. Best I've seen for ages, I'm almost seeing the same figures as Corey at times.

Fish

Link to comment
Share on other sites

  • 2 weeks later...

I've just bought a scan gauge, so will see over next few months if that helps my MPG any more.

Link to comment
Share on other sites

  • 3 weeks later...

Currently averaging 52mpg ...IQ2 auto

Link to comment
Share on other sites

My wife filled her IQ2 Auto to the brim when she bought it, reset trip A to zero, trip A now shows 297.4 miles and she has just filled it to the brim again, according to Fuely that's 57.1MPG, that's exactly the same as the displayed Average MPG.

She is returning to driving after many years so her driving style is "steady", all her journeys are about 10 to 30 miles and mostly in built up areas.

I think for this type of driving 57.1MPG is excellent, especially for a new car.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share






×
×
  • Create New...




Forums


News


Membership