What MPG are you getting from your Honda Jazz ?

[EdinJazz]

2015 1.4 . I get 46mpg when urban driving, 48mpg on the motorway and have even got 52mpg on a motorway cruising at 60mph.

[BrummPopBang]

After setting the tappets on my Jazz (Jazz 2012 5dr Hatchback 1.4 I-Vtech ES L13Z1, 124000 miles) I realised the fuel usage behaviour had changed.

This is a snippet from a my post about the fun of setting the tappets and the apparent affects on fuel efficiency.

https://clubjazz.org/forum/index.php?topic=13644.msg151392#msg151392


"About a year ago I went from Camberley on the M3 to Southampton - it's downhill by about 90m so I believe even though there are some significant ups and downs near Southampton and the display showed 69mpg. My calculations show that the reading at that milage is about 7mpg high ie 62mpg true. I drove back (up hill this time) to give 62mpg (or 55mpg true).

Back to the present - I set the tappets and gapped the plugs and did a test drive. I wasn't expecting it but I thought "it's quieter - more like a sewing machine". Within the week I drove from Camberley to Keswick in the Lakes (320miles) and recorded 62mpg (55mpg true) there (up hill again) and a week later 64mpg back (57mpg true).

What also seems to have happened is the mpg local driving rises far more quickly to the mid-50s which is nearer to 50mpg. So its more efficient more quickly but it doesn't get as high with the tappets set correctly."

[Lord Voltermore]

After setting the tappets on my Jazz (Jazz 2012 5dr Hatchback 1.4 I-Vtech ES L13Z1, 124000 miles) I realised the fuel usage behaviour had changed.

This is a snippet from a my post about the fun of setting the tappets and the apparent affects on fuel efficiency.

https://clubjazz.org/forum/index.php?topic=13644.msg151392#msg151392


"About a year ago I went from Camberley on the M3 to Southampton - it's downhill by about 90m so I believe even though there are some significant ups and downs near Southampton and the display showed 69mpg. My calculations show that the reading at that milage is about 7mpg high ie 62mpg true. I drove back (up hill this time) to give 62mpg (or 55mpg true).

Back to the present - I set the tappets and gapped the plugs and did a test drive. I wasn't expecting it but I thought "it's quieter - more like a sewing machine". Within the week I drove from Camberley to Keswick in the Lakes (320miles) and recorded 62mpg (55mpg true) there (up hill again) and a week later 64mpg back (57mpg true).

What also seems to have happened is the mpg local driving rises far more quickly to the mid-50s which is nearer to 50mpg. So its more efficient more quickly but it doesn't get as high with the tappets set correctly."

I dont dispute that adjusting the tappets reduces noise,  but I'm not so convinced this ,or plug gaps, has affected motorway fuel consumption significantly.  Camberley is 88 metres above sea level, Southampton up to 82 metres and Keswick  140 metres.  So despite how it may seem for certain stretches , uphill and downhill  pretty much average themselves out.  The difference between outward  and return journey probably has more to do with the prevailing wind direction.  Cars use quite a lot more fuel  against a headwind than when its assisting them as a tailwind.   Even in light winds not noticeable to the driver.   Air temperature can make a difference to the  same journey summer vs winter.  Colder air is denser increasing wind resistance. 
Also tyre rolling resistance increases if the treads are having to disperse rainwater.   

[BrummPopBang]

I think those comments are fair enough. Although an IC engine will be more efficient with colder air intake, in the real world, a cold engine will drag more until it's warmed up; so again, it's pluses and minuses with so many factors.

What setting the tappets showed me is that a better system than using feeler gaugers is required, not only from the repeatability perspective but also from the speed of setting sixteen of them with a decent degree of accuracy.

[pramodhonda]

I am getting average 10 to 11 km per liter in in India on highway . And A full tank fill consumes in 330 kms in city drive condition in my jazz 1.2 ivtec 2009 model.
Recently I have cleaned throttle body and MAP and MAF sensor incl O2 sensor.
Can anyone help me how to improve mileage .

[RugOnBackSeatAndThermos]

My recently purchased low mileage 2014 EX model with the so called 1.4 litre engine is providing 52.5 mpg overall according to the car readout. The car is mainly used for rural A and B road motoring with some city stop start. The motoring readout seems to be only slightly more optimistic than reality. My Nissan Notes with a 1.2 supercharged 3 cylinder engine have had wildly optimistic readouts achieving only 47 mpg and not 62 mpg claimed!  My Mitsubishi Colt 1.3 Cleartec was bang on accurate at 52 mpg, but could achieve 60 mpg on steady motorway cruising. I was expecting the Jazz to be less economical than either the Note or my Mitsubishi Colt, but am pleased that in practice it is more economical than the Note with a smoother quieter ride on our badly repaired roads. The Note and the Colt needs less gear changing than the Jazz and the Note better and quieter on Motorways between 60 and 70mph.

[Wastrel]

New member here, thanks for the ad guys, I drive a bog standard 1.4Si on a 13 plate, I`ve owned it for 11 years, 17k miles on it when I bought it & sitting at 85? right now, as for mpg, I average around 46-50 around town, about 54 on a decent m/way or dual carriage way run where I simply set my cruise control to 55mph.

[yg1r]

After 37k km logging through spritmonitor.de I get 7lt/100km on my ES 1.4. I recently got cruise control retrofitted, so it would be interesting to see what kind of impact does that have on consumption from now on

[OilySock]

Wow, there's some interesting figures in this thread & I think my new Jazz (new-to-me anyhow) must be the thirstiest on on the planet!

Its a 88k mile 2012 1.4 manual gearbox iVtec & I've owned it for three months. I've driven 2023 miles and overall consumption works out at 37.3 mpg. Although it's been mainly stop-start city driving with a little motorway it's a bit disappointing as I'm told I drive like a Granny.
About two months ago I changed the oil & all the filters so now I'll be checking the spark plugs & will see if a brake is binding. Does anyone have any other advice?

Cheers

[RugOnBackSeatAndThermos]

I wouldn’t be too deflated by my mpg figures Oily Sock  if you are frequently commuting short mileages in a big city where the engine isn’t warming up. I live in a rural  location with no immediate stop starts close to home. So my cars get warmed up very quickly.  You may want to consider whether the engine isn’t getting up to temperature fast enough if the thermostat is sticking open….
Also in my experience if you have the air con switched on all the time this can appreciably affect affect fuel consumption on many cars. For example my Mitsubishi Colt four cylinder twin cam 1332 cc engine would regularly achieve 60 mpg with air con off on a regular 70 mile journey. On the same journey with air con on it would return 52mpg. The Mk2 1.4 Jazz will achieve 58 mpg on the same journey with air con off and 53mpg with air con on. The 3 cylinder supercharged 1.2 litre Note achieves 51mpg air con off and 48 mpg air con on. However if I enable the supercharger for something approaching tolerable performance it really takes its toll on fuel consumption. If I use the Note for city travel with air con on then it’s only achieving 41 mpg. In my youth these would have been unimaginably frugal figures. In my 20’s I owned a Vanden Plas 4 litre Princess R for 5 years. Its six cylinder Rolls Royce 3909cc engine achieved 17.6 mpg and it made little difference whether it was in town or rural. I once achieved 21.3 mpg on a 150 mile night time trip on the M4 keeping the speed at around 55 mph and I was delighted.  The Saab 99 and two Saab 900s  I owned successively for the next 25 years rarely achieved 30mpg… A total of over 450,000 miles between these four cars. However the Saabs and the Vanden Plas were all completely reliable. I put this reliability down to maintaining the cars wherever possible myself at home and never trusting garages to source parts! I always change the oil at 7000 miles, flushing the engine with some fresh oil and always change air filters more than necessary. Although a gas guzzler the Vanden Plas Princess Rolls was in some ways the most sustainable vehicle I have owned. It cost me less overall in running costs than all the other cars as I sold it for far more than I paid for it, and the profit wiped out the costs of its fuel and (home) servicing and parts…

[Synchrotron]

Hi all,

In my first 250 miles I have averaged 48.6 mpg on mostly-motorway driving, which sounds a little low, considering some of the figures here. Is this value low, do you reckon, or somewhat reasonable?

Admittedly, I’m still getting used to my Jazz, so probably driving far from optimally, and I have the EX version, with 16” rims, which I know give worse mpg. The dealer I got the car from also put on four brand new tyres, but the absolute cheapest, so that is likely not helping either!

I was wondering whether ageing spark plugs might be having an influence too, as I can’t find any obvious record in the paperwork of them having been replaced (I know they are iridium and meant to last, but the car has nearly 100k miles on the clock). The engine sounds perfect, no misfires or rattles, etc., so no obvious signs of failing plugs.

Swapping the tyres seems very wasteful, so that will likely have to wait, but the plugs I will probably try to replace quite soon.

Any insight welcome!