What MPG are you getting from your Mk1 Honda Jazz ?

[150234]

Had to refill my tank again this morning. That is 6 top-ups this month with a total of 38.9 gallons (177 litres).
This tankful returned 59.2 mpg and the last 10 top-ups, as calculated by Fuelly, works out at 53.9 mpg.

How the hell are you getting 59.2 mpg? I can get 49 mpg on the motorway if I go at around 55 - 60 mph, but get me on some A roads and I am down to about 35 mpg. At the peak of my adventures, I was filling up from light on to full twice a week and was doing that for around 4 months. I was going through petrol like it was water.

[Jocko]

I have a ScanGauge E fitted which shows me instantaneous mpg. I can see when it is in Deceleration Fuel Cut Off mode, which I make as much use of as I can. In DFCO the car uses no petrol. I also do a little freewheeling in Neutral when appropriate. I try to avoid using the brakes, depending instead on anticipation. I keep the tyre pressures up about 3 psi. Basically just mild hypermiling tricks. My best ever tank full was 69.9 mpg calculated.

[Jocko]

I got a very pleasant surprise today, when I refilled the tank. The Fibometer was showing 62.9 mpg, and I reckoned it was a mile out, but the calculated figure was 60.5 mpg. This came as a real surprise as I have been driving back from Danderhall every afternoon and I seem to spend as much time in crawling traffic as I do driving on the open road.
The Edinburgh City Bypass is a nightmare (Scotland's M25) and now the Queensferry Crossing is an aerial traffic jam, every trip.

[Jocko]

The fourth tankful this month and as expected the petrol was up again. 127.7p/litre at Morrisons. Luckily I am getting great mpg at the moment. This time it was 61.6 mpg (Fibometer 62.9).
For the last 10 fuel-ups, Fuelly reckons I have averaged 58.9 mpg.

[Droneranger]

My apologies.

[guest4871]

Each to their own. I know you are not setting out to be harsh.

Jocko has a special enjoyment in maximising his MPG. I enjoy him sharing his enthusiasm and reading about his results and techniques.

I would never have the patience he has to do what he does even if I understood how he does it. I do admire him for his achievements.

Different horses, different courses?

[Jocko]

I do not really mean to be harsh, but i do not care what the MPG of my cars is, I also do not care very much about the price of petrol.
The First Gen Jazz will go to 30mph in first gear, it will go to 55mph in second, and third will take it up to the legal limit.

I never did either, until getting the Jazz. Up until then I just put petrol in when I needed it and drove how I felt like it on the day.
Then I got the Jazz and I suddenly found I was getting almost twice the mpg of my Volvo which the Jazz replaced. At about the same time I read an article on Hypermiling and was given my ScanGauge E. This set me on a path to trying to maximise my mpg, purely as a game. I enjoy video games and this was a video game I could do in real life. Continually trying to beat my high score.
As for the price of petrol, it is what it is. So far this month I have filled the tank four times and I will have another tankful before July arrives. I have so far this month spent £157 on petrol. As an OAP this is more or less a quarter of my State Pension for June, so the increasing price does trouble me. It is not critical. I just wish it was cheaper.

[peteo48]

I monitor my mpg even though cost is not really any factor given the tiny annual mileage I do these days. I took delivery of this car on the 29th of January last year and, as of today, it's just past 3,000 miles (in nearly 18 months).

That's not the same for everybody though. Having to do high mileages then the price of petrol is definitely a factor. It's noticeable, too, that rising fuel prices have quite an impact on the inflation rate.

[150234]

So I never look at my MPG but on the duel carriageway today I averaged around 46mpg at around 70mph. This was with 5 people in the car on a fairly hilly stretch of duel carriageway. Not to bad considering the age of the car (2003 1st gen Jazz), that it was heavily loaded and the fact that I love to overtake as many cars as possbile in a journey.

As a previous poster has said the mk1 jazz will do 30mph in 1st, 60mph in 2nd and 80 in 3rd and that's all anyone needs to know as far as fuel economy is concerned. It's always funny to get someone in the car who is the type of person that is afraid to rev their car above say 4k rpm as then theres me bouncing of the red line like it's a trampoline.

In the later part of last year I was going through petrol like it was water and wasn't paying attention to what I was spending. The girl I was seeing was giving me fuel money as well and once I added it up I was spending around 400 quid a month on fuel. Which looking back was worth it but it certainly put my 17 year old through it's paces. 

[culzean]

So I never look at my MPG but on the duel carriageway today I averaged around 46mpg at around 70mph. This was with 5 people in the car on a fairly hilly stretch of duel carriageway. Not to bad considering the age of the car (2003 1st gen Jazz), that it was heavily loaded and the fact that I love to overtake as many cars as possbile in a journey.

As a previous poster has said the mk1 jazz will do 30mph in 1st, 60mph in 2nd and 80 in 3rd and that's all anyone needs to know as far as fuel economy is concerned. It's always funny to get someone in the car who is the type of person that is afraid to rev their car above say 4k rpm as then theres me bouncing of the red line like it's a trampoline.

In the later part of last year I was going through petrol like it was water and wasn't paying attention to what I was spending. The girl I was seeing was giving me fuel money as well and once I added it up I was spending around 400 quid a month on fuel. Which looking back was worth it but it certainly put my 17 year old through it's paces.

No good revving MK1 DSI above about 4,500 rpm as it 'runs out of breath'  (  it is an 8 valve engine ).  The DSI engine does better when kept below those revs and is much more drivable at low revs than the VTEC MK2.

[Jocko]

Today we were flitting some furniture so once the van set off we had to, "My Old Man, said follow the van", and catch up the 10 minutes start they had. It was a 98% dual carriageway/motorway journey and I kept it on the limit, traffic allowing, all the way. According to my ScanGauge E (normally within 0.5 mpg of the calculated figure), I averaged 51 mpg for the 40-mile trip. And we never caught up with the van. We arrived first because they took a different route!

[150234]

So I never look at my MPG but on the duel carriageway today I averaged around 46mpg at around 70mph. This was with 5 people in the car on a fairly hilly stretch of duel carriageway. Not to bad considering the age of the car (2003 1st gen Jazz), that it was heavily loaded and the fact that I love to overtake as many cars as possbile in a journey.

As a previous poster has said the mk1 jazz will do 30mph in 1st, 60mph in 2nd and 80 in 3rd and that's all anyone needs to know as far as fuel economy is concerned. It's always funny to get someone in the car who is the type of person that is afraid to rev their car above say 4k rpm as then theres me bouncing of the red line like it's a trampoline.

In the later part of last year I was going through petrol like it was water and wasn't paying attention to what I was spending. The girl I was seeing was giving me fuel money as well and once I added it up I was spending around 400 quid a month on fuel. Which looking back was worth it but it certainly put my 17 year old through it's paces.

No good revving MK1 DSI above about 4,500 rpm as it 'runs out of breath'  (  it is an 8 valve engine ).  The DSI engine does better when kept below those revs and is much more drivable at low revs than the VTEC MK2.

That's interesting. I always find that if you wind the car out to redline in 1st then change into 2nd you seem to hit a deadspot in the power for about 10mph. Almost like 2nd gear is too high in comparison to 1st. The engine in my Jazz doesn't seem to do anything until about 3,000 rpm and 30 mph in second (the point at which 1st runs out) is well below that hence the deadspot in the power delivery that I have. If it wasn't for that dead spot from 1st to 2nd it would actually be fairly rapid up to 60mph as you would stay in 2nd from 30 to 60mph.

[150234]

So I never look at my MPG but on the duel carriageway today I averaged around 46mpg at around 70mph. This was with 5 people in the car on a fairly hilly stretch of duel carriageway. Not to bad considering the age of the car (2003 1st gen Jazz), that it was heavily loaded and the fact that I love to overtake as many cars as possbile in a journey.

As a previous poster has said the mk1 jazz will do 30mph in 1st, 60mph in 2nd and 80 in 3rd and that's all anyone needs to know as far as fuel economy is concerned. It's always funny to get someone in the car who is the type of person that is afraid to rev their car above say 4k rpm as then theres me bouncing of the red line like it's a trampoline.

In the later part of last year I was going through petrol like it was water and wasn't paying attention to what I was spending. The girl I was seeing was giving me fuel money as well and once I added it up I was spending around 400 quid a month on fuel. Which looking back was worth it but it certainly put my 17 year old through it's paces.

No good revving MK1 DSI above about 4,500 rpm as it 'runs out of breath'  (  it is an 8 valve engine ).  The DSI engine does better when kept below those revs and is much more drivable at low revs than the VTEC MK2.

As my Jazz has spent it's entire life before me pootling about, i like to drive the car in a spirited manner when outside of the 30mph limit. I have been driving the Civic type R for 17 years and treat my Jazz the same, I have found it to be quite capable if driven hard.
I have not experienced the engine running out of breath, even when driving up a steep bendy hill pretty much flat out.

What exactly do we mean by "run out of breath"? If you want to get away quick surely running up to redline in 3rd at 80mph is better than say changing gear into 4th way back at 4500rpm? Yes 4,500 rpm may be where the power is but surely being in a lower gear makes up for that in terms of the quickest way to get to 80?

[culzean]

What exactly do we mean by "run out of breath"? If you want to get away quick surely running up to redline in 3rd at 80mph is better than say changing gear into 4th way back at 4500rpm? Yes 4,500 rpm may be where the power is but surely being in a lower gear makes up for that in terms of the quickest way to get to 80?

The difference between 'flexible' and 'peaky' engine  --  the MK1 DSI engine,  being 2 valves per cylinder and no ability to alter valve timing with revs is 'flexible' and in my experience much nicer to drive everyday than the 'peaky' VTEC MK2 Jazz,  which ( from experience ) feels pretty gutless below 2500 revs but has a higher specific power and because of the VTEC the power continues to build in proportion to revs.  The problem you have highlighted about large 'gap' between 1st and 2nd gear is more of a problem on the VTEC than the iDSI

https://mechanics.stackexchange.com/questions/7922/engine-power-specification-at-different-rpm

[150234]

What exactly do we mean by "run out of breath"? If you want to get away quick surely running up to redline in 3rd at 80mph is better than say changing gear into 4th way back at 4500rpm? Yes 4,500 rpm may be where the power is but surely being in a lower gear makes up for that in terms of the quickest way to get to 80?

The difference between 'flexible' and 'peaky' engine  --  the MK1 DSI engine,  being 2 valves per cylinder and no ability to alter valve timing with revs is 'flexible' and in my experience much nicer to drive everyday than the 'peaky' VTEC MK2 Jazz,  which ( from experience ) feels pretty gutless below 2500 revs but has a higher specific power and because of the VTEC the power continues to build in proportion to revs.  The problem you have highlighted about large 'gap' between 1st and 2nd gear is more of a problem on the VTEC than the iDSI

https://mechanics.stackexchange.com/questions/7922/engine-power-specification-at-different-rpm

This might be specific to my engine in my car or it maybe a more general thing but I find that, especially in the higher gears, the engine performs and responds better if you "feed" the throttle over 2 seconds or so than if you just mash it. Overtaking on the motorway is an example of this. If I sit at 80 and wish to overtake I will struggle to really get moving if I mash it but if I take a few seconds to feed it it's almost like I am giving the engine chance to react to my input. Still only 84hp mind you so it's never going to be quick, but it's certainly capable of being nippy if you drive it hard. The car is also very light which helps althought it is a bit like driving a kite when it's windy.

Is thing something you have noticed on the VTEC engine in the mk2 Jazz?