How to improve fuel economy on a 1.9 Z3????

davegrehan1 · Post by **davegrehan1** » Mon 12 May, 2008 18:43

Hi All,

Just purchased a 1.9 Z3 a 02 had 56k on it 3 weeks ago when I get it now has 58.6k on the clock from mainly driving the weekends.Anyway love the car and in it every chance I get but I'm looking for some help on how to improve the fuel economy. From reading the forums some people are getting 30-35 mpg? I reckon my car is averaging 25-27 mpg? The guy I bought it from reckoned thats what he was getting and told me he never really pushed the car that hard as he had been left in a bad way from a crash from a previous car and was always afraid to drive hard in the Z????Should this make a difference that the car was spoiled most of its life?Apart from driving in socks to improve my heavy boots issue I'm fresh out of ideas.I filled the tank on sunday and have done 121 miles and have half a thank left so may be my math is incorrect and I'm getting more bang for my buck.Its disappointing to see the needle in the fuel gauge head in the wrong direction when I push it on.

Any help would be appreciated.

Dave

Post by **Robert T** » Mon 12 May, 2008 18:56

Hi Dave and welcome to the forum.

It seems to be very dependant upon what kind of driving you do. Round town I get about 28mpg out of min, but on a long easy motorway run I have managed 43mpg.

I found that running mine on better fuel (I use V-Power) helps with the economy and perks her up a bit in the mid-range.

I don't have an OBC, so I have to work mine out by hand - I tend to fill up when the needle drops just below a quarter and brim the tank - I usually get between 220 and 250 miles on that - just over 300 on a complete tank. One thing to note is that you get better economy if you use imperial gallons instead of US ones.

Cheers R.

ZedBar · Post by **ZedBar** » Mon 12 May, 2008 21:13

Hi Dave

I have a 51 reg 1.9 sport running on shell v-power, averaging between 24 to 28 mpg. I keep telling myself to drive moderately to get better fuel consumption but I can't, when I get in the zed I feel have to drive it with spirit hence the low mpg. I know this doesn't help but if you do find a solution let me know as I would love to get more mpg especially with the price of petrol these days.

Dave

Justin Time · Post by **Justin Time** » Mon 12 May, 2008 21:17

Dave, I had the same mpg with my 1.9, though most of my driving was around town. Never increased it as I only owned it 2 months before it died.

With the same driving, in my 2.0, I'm getting 30-32mpg. Must be due to the different engine types (yours - M44, mine - M52).

phb10186 · Post by **phb10186** » Mon 12 May, 2008 21:29

I would have expected better urban MPG's from the 1.9 TBH.

It is not always the case that a smaller engine is more economical as you tend to give it more gas to make up for the lack of torque.... Probably.

My Honda Prelude 2.2 VTI did a lot less MPG's than my 2.8 Z3.... I put it down to torque availability.

Lazeodoom · Post by **Lazeodoom** » Mon 12 May, 2008 22:43

I get 250-300 miles or so to a full tank in my 1.9. I must admit though that some days my right foot is heavier, especially with the top down! I can only suggest that fuel economy isn't the 'be all and end all' in a sports car. We bought Zeds for the way they look, sound and make us feel, rather than for fuel economy! I certainly never felt the need for a G-Wiz!

c_w · Post by **c_w** » Tue 13 May, 2008 08:22

It appears like the 2.8 / 3.0 is the best engine to get if you get the same economy from them but a lot more power!!

ZedMatt · Post by **ZedMatt** » Tue 13 May, 2008 09:08

phb10186 wrote:It is not always the case that a smaller engine is more economical as you tend to give it more gas to make up for the lack of torque.... Probably.

Aren't the 1.9 and 2.0, the same capacity, but 12v vs. 24v? But the second half my still be valid - having to give more beans for the grin factor. I'm yet to find out my consumption figures, will have to wait for a "brave moment" for that calculation!

Using a higher RON fuel (I'm ONLY using V Power too) will help both your mpg and engine. Other possible helps include tracking, tyres and removal of unnecessary weight.

Anybody heard of a remap specifically for mpg improvement?

c_w · Post by **c_w** » Tue 13 May, 2008 09:34

The 2.0 is a straight 6.

Austin Powers · Post by **Austin Powers** » Tue 13 May, 2008 10:36

c_w wrote:It appears like the 2.8 / 3.0 is the best engine to get if you get the same economy from them but a lot more power!!

Exactly. Would add the 2,2 into this batch tho.

BW
Austin

Justin Time · Post by **Justin Time** » Tue 13 May, 2008 13:27

ZedMatt wrote:Aren't the 1.9 and 2.0, the same capacity, but 12v vs. 24v?

Z3 Engine stats along with some other useful info

The other plus side of the 6 cyl vs 4 is the exhaust note. You really do notice it when you change engine types.

ZedMatt · Post by **ZedMatt** » Tue 13 May, 2008 14:08

Justin Time wrote:
ZedMatt wrote:Aren't the 1.9 and 2.0, the same capacity, but 12v vs. 24v?
Z3 Engine stats along with some other useful info

Yeah, I really don't know where that nugget of non-truth came from then

BonBon · Post by **BonBon** » Tue 13 May, 2008 14:13

I'm getting 28 mpg pretty consistently on a '98 Auto (M44) with 96 Octane. (50% urban).
Will now test 98 Octane (as I also want to clean off the gook presumably on fuel gauge)

henrycrun · Post by **henrycrun** » Tue 13 May, 2008 17:18

Check your tyre pressures ? Try running at 32 - 34 psi

davegrehan1 · Post by **davegrehan1** » Tue 13 May, 2008 17:18

Cheers all,

Quote on quote "We all know that the investment in a car is the fun enjoyed and not the cost" I think I will be adopting the above as my trail of thought from now on.I drove home this with the top down the sun beating down wasn't paying a whole attention to the petrol gauge and dont intend to from now on.

Guest · Post by **Guest** » Wed 14 May, 2008 08:59

Make sure that your brake pads are not sticking to their carrier, which will cause brake binding and increase fuel consumption a little.

Good fuel consumption is a matter of making sure the car is in optimum condition, and also driving it smoothly. Where and how you drive is the key consideration - if you want to spend your life in a traffic light grand prix, or do lots of short cold runs, don't expect good fuel consumption.

At 80 mph on French autoroutes my 2.8 usually gives about 34 mpg, with 38 to 40 mpg on secondary roads at about 60 mph. UK motorways give about 37 mpg.

I find the trip computer to be pretty accurate, a recent long run showing 36.6 mpg and calculation about 36 mpg (imperial gallons)

BonBon · Post by **BonBon** » Wed 14 May, 2008 09:39

.......and wat does it do when you drive in the real world? (inner city)
24-26MPG ?

Guest · Post by **Guest** » Wed 14 May, 2008 10:09

If an inner city counts with you as being the 'Real World' then you have my condolences! I don't normally drive in such awful places, unless you count the odd trip around the Paris Boulevard Peripherique, which is usually mobile and pretty painless. The last time I drove on le Peripherique it was a 45/50 mph affair, and le Red Zed returned over 40 mpg.

If you have to drive in stop-go conditions, then I would imagine that a 2.8, like any other car, will return pretty low consumption figures, but don't use that as an indication of its consumption when used in good conditions. The UK is a pretty dire place, which does not bring out the best in either people or cars.

In MY real world a trip to the nearest big town is 12 miles , where 50/60 mph around the empty twisty roads is fun. Even in summer, on a 20 mile run for Sunday lunch we seldom see another car.

On my last trip across rural France trip I covered many miles without seeing another car - in front or behind.

That's the real world - cities are a fabrication, designed for those who have to work in them!

BonBon · Post by **BonBon** » Wed 14 May, 2008 13:13

Interesting view of the world......

...but presumably you also had to work in one of those awful urgh "cities" until you were able to retire.

With respect to the UK - it's not all bad. It produces some great engineers, dedicated hobbyists and at least one good wife.

c_w · Post by **c_w** » Wed 14 May, 2008 13:29

BonBon wrote:Interesting view of the world......

...but presumably you also had to work in one of those awful urgh "cities" until you were able to retire.

With respect to the UK - it's not all bad. It produces some great engineers, dedicated hobbyists and at least one good wife.

You're right, it's not all bad, perhaps Mike hasn't really driven much in the UK. Rural UK/rural France, if you drove in North Yorks, parts of East Anglia, Wales, Scotland etc you "might not see another car" for a while on some of the greatest roads, although it has to be said there are some huge areas of barely populated in France, but there are also some big cities. Paris Perhipherique is always one to avoid just like the M25 at peak times, massive tailbacks on both if there is an accident. And Paris is becoming a no go zone for cars just like London, neither of which are the best places to drive in anyway unless you "have" to.

Lazeodoom · Post by **Lazeodoom** » Wed 14 May, 2008 15:03

To be honest I quite like it driving from Brum to other less local places via smaller roads. If there is a car ahead its almost always slower, and a pleasure to overtake!

By the way, I'll be experiencing the best journey I ever made in the Zed once more next month, as I go from Central Birmingham to the Isle of Wight via Evesham, Cotswolds, Oxford, Winchester and Southampton. 200 miles or so of (hopefully) glorious hood down weather, with my new stereo cranked up when I'm out of town, driving through as much winding countryside as possible until Oxford, and then the almost perfectly straight A34 all the way to Winchester.

How to improve fuel economy in a 1.9 Zed? Don't let me drive it!

Guest · Post by **Guest** » Thu 15 May, 2008 08:36

There are other ways of making a decent living, than working in a city - I used to go to sea for mine. I have the feeling that while Britain has produced some of the best engineers, such activity is now over, with the decline of our manufacturing industry - but at least it has given us a legacy in the form of some wonderful museums.

In contrast, France still lhas a vibrant manufacturing sector, able to go it alone on projects such as combat aircraft, nuclear power stations etc. They even still have a widespread system of apprentice training. Even our local Polish builder had to gain acceptance in the French system before he was qualified to be set loose on our house etc, whereas in the UK anyone can be whatever they claim to be.

phb10186 · Post by **phb10186** » Thu 22 May, 2008 17:49

Lazeodoom wrote:I get 250-300 miles or so to a full tank in my 1.9. I must admit though that some days my right foot is heavier, especially with the top down! I can only suggest that fuel economy isn't the 'be all and end all' in a sports car. We bought Zeds for the way they look, sound and make us feel, rather than for fuel economy! I certainly never felt the need for a G-Wiz!

You might if the latest economic forecasts and oil proce predictions are anything to go by.

phb10186 · Post by **phb10186** » Thu 22 May, 2008 18:06

Mike Fishwick wrote:The UK is a pretty dire place, which does not bring out the best in either people or cars.

I think that the UK is a beautiful place actually. There may be a few trouble makers and some bad parts, but you would get that anywhere. Suburban North-West London life serves me very well thank you.

Lazeodoom · Post by **Lazeodoom** » Thu 22 May, 2008 18:36

I'll second the above: Birimgham suits me just fine, I'm quite a big fan of crowded cities and 24 hr living!

Franco · Post by **Franco** » Fri 23 May, 2008 18:39

Having just returned from a 1200 mile trip to the Loire and chasing Z!'s and big brother 2.8's and even a M around the local roads I managed 37.6 mpg from my 1.9.
Must agree with Mike big towns apart, motoring in France is a pleasure than can be rarely had in the UK. I have spent some 20 years driving as a part of my job all over the UK and it became a pain. In France it's a joy and is to be recommended.

BonBon · Post by **BonBon** » Fri 30 May, 2008 12:43

[I'm getting 28 mpg pretty consistently on a '98 Auto (M44) with 96 Octane. (50% urban).
Will now test 98 Octane (as I also want to clean off the gook presumably on fuel gauge) ]

Well - after a few tanks of 98 octane the average MPG has suprisingly gone down from 28 to 26.5.
On the other hand, subjectively, it feels like I'll also lost some bhp/kick in low gear. Does not pay at 15% price premium for 98 vs 95 here.[/quote]

mattdedasc · Post by **mattdedasc** » Tue 03 Jun, 2008 18:33

Mike Fishwick wrote:Make sure that your brake pads are not sticking to their carrier, which will cause brake binding and increase fuel consumption a little.

)

I have this very problem. That, and a wheel bearing to change.

it's getting expensive to run that Z

burmagirl · Post by **burmagirl** » Mon 09 Jun, 2008 22:15

I usd to get an avrage of 270 miles to the tank in my 1.9. In the 3.0 I average - according to the trip computer - 25 mpg. I seem to remember people posting on here that they'd managed as much as 30mpg in an M, so mine seems low; even on long motorway journeys I can't get it over about 26.4 mpg.

burmagirl

BonBon · Post by **BonBon** » Thu 31 Jul, 2008 12:19

addendum:
Low tire pressure - 10% hit
Full A/C - 10% hit (may not be relevant in the UK

)

c_w · Post by **c_w** » Thu 31 Jul, 2008 12:26

Most of the bad urban mpg figures (assuming it's not sitting in gridlock) are as a result of too-harsh acceleration and the way people read, or rather don't read, the road. Some people just accelerate hard all the time or use excessive revs, and can't see that there's no need to be still accelerating up to that red light.

I get dissappointed if I get 25mpg in the M

but as most of the time I drive the car it's longer drives I usually aim for high 20s/30mpg. 36mpg is my record average though.

Guest · Post by **Guest** » Thu 31 Jul, 2008 13:31

Probably the most common cause of poor fuel consumption is the means of calulating it. Don't trust your trip computer until it has been checked on a distance divided by fuel used basis - do NOT use the usual rubbish that it cost so much to fill up, so you have used so many gallons!

Fill to the top, or as close as possible - this is almost to the filler neck. Reset the trip indicator and the trip computer, and drive until the fuel gauge gets to the 'quarter full' mark. Then refill to the filler neck, and log the amount of fuel you have put in. Also log the average fuel consumption shown on the trip computer.

Go home, and calculate the actual fuel consumption, dividing the mileage reading by the amount of fuel used - remember that one imperial gallon equals 4.5 litres.

Now compare this actual average consumption to that shown by the trip computer, and you will know how accurate it is. For even greater accuracy you could instead put a measured amount of fuel - say 30 litres - into the tank, and log this, adding it to the amount used to fill the tank next time.

Also compare the amount of fuel put back in to the fuel guage reading, so you know how much fuel you had left out of your original 55 litres.

By filling up at different guage readings you can get a very good idea of how much is left at each calibration, so you know how far you can push things if running low.

My tank takes the following, based on a theorectical 55 litres capacity - in practical terms this means there will always be about half a gallon which you cannot get out of it:

Full – 12 gallons (55 litres)
Three-quarters – 9 gallons (40.5 litres)
Half – 7 gallons (31.5 litres)
Quarter – 4 gallons (18 litres)
Red sector (top) 3 gallons 13.5 litres)
Red sector (mid) & warning lamp – 2 gallons (9 litres)
Empty – 1 gallon (4.5 litres)

I agree with CW, that lots of people seem to feel obliged to accelerate and brake harshly, just because they have a powerful car. They forget that it just shows they lack maturity, judgement, and mechanical sympathy.

If you use your vision and anticipation, and also drive smoothly, your fuel consumption will improve, wear and tear on the car will reduce, and - believe it or not - your driving pleasure will also increase.

dalemiller · Post by **dalemiller** » Thu 31 Jul, 2008 14:02

Here's what I did recently, and my economy on my 2.8 went from 30 to 34 MPG;

Mobil one fully synthetic oil
New fuel filter
Redex fuel system treatment.

No need to expensive petrol or anything, I use ASDA unleaded (includes the detergent & is cheaper!)

Just my $0.02, but it worked for me!

zroadster.net

How to improve fuel economy on a 1.9 Z3????

How to improve fuel economy on a 1.9 Z3????

Economy

Real?

Off-topic, but -

Re: Real?

98 Octane

Re: Economy

Ps

mpg