mileage 20l/100??

[ellie]

Hi all
I have just bought a 2005 liberty 3.0r. After only 100kms I have used a half tank - the meter says the mileage is 20l/100kms. All my driving has been short city trips - however can anyone tell me whether the fuel usage could possibly be that high even for short city driving ??! Thanks.

[jdm rsk]

wow i thaught my car was bad at around 14.5 lt/100...yikes

[smythie]

If you are sitting idling for long periods (i.e. sitting in traffic jams) it is quite easy to get up to that sort of (lack of) economy. If you are hard on the throttle you will also hurt your economy. If your car doesn't get out of the CBD you won't see reasonable economy.

This applies to any petrol engined car, not just the 3.0R. 20l/100km does sound a bit high but I wouldn't be calling it impossible if the above are happening

[GTB Liberty]

Considering I've seen instantaneous fuel usage number at well over 500l per 100 Km - consider yourself fortunate your average is only 20L.

[ellie]

Thanks for all your replies - sounds like it might be the inner city driving issue. Am wondering however whether it could be to do with tuning? If it was tuned for high performance by the previous owner would it make a difference to fuel usage?

[teK--]

Short city driving... does that mean that your trip ends before the engine is up to temp, and by the next time you drive it's cooled down again? This would explain a lot since the fueling is very rich until the engine is up to temp. Other than that, your typical stop start CBD driving kills anything but a Prius.

[ellie]

Sorry teK - please excuse my ignorance - but what does up to temp mean? Many of my trips are only 2 to 5 kms, stop start - and yes the engine would have cooled in between trips.

[teK--]

It takes a good 10mins of driving to get the engine oil up to operating temperature. Until then the fuel economy is not at it's optimal level.

When the coolant temp needle is halway it is *roughly* at operating temp (it is very dumbed down), but the engine oil often takes twice the amount of that time, to reach 85-90degC (optimal).

Idling in stop start traffic does not warm up the engine anywhere near as quickly as going at a steady pace.

[ellie]

Thanks very much (dumbed down is good for me!) - all makes sense. Will try to average in some longer trips and that should confirm the answer.

[nico]

Speaking from experience (new engine fitted), if you are continually driving short trips without warming your engine up, not only will you get horrendous economy (20l/100k's) but risk serious damage to your engine.

I'd recommend letting your engine warm for a couple of minutes if you are only going 2-5k's.....or get a pushy

[BUDDAH]

Hi all
I have just bought a 2005 liberty 3.0r. After only 100kms I have used a half tank - the meter says the mileage is 20l/100kms. All my driving has been short city trips - however can anyone tell me whether the fuel usage could possibly be that high even for short city driving ??! Thanks.

Some thing is definitely wrong I drive (07 3RB auto ) hills area to Botany using Parramatta Rd peak 70k round trip every day and average 470k to a tank and I dont pussy foot around
And tow a 1200kg boat to Hawks Nest and back most weekends during summer with car full of crap and average 12/100kms

[smythie]

very different driving conditions if you bother to read the OP's posts above

[Lukovitch]

My old 2.5i (2006) had an intermittent dodgy fuel gauge, every now and then would say I'd used a lot more fuel than I had and economy would jump through the roof, then settle back to where it should have been. Perhaps this is a similar scenario?

[The Sean]

I can see those figures as foreseeable for the trips you do.

I do 15km drives in Sydney peak traffic and average 14km/100 driving like my Nan and about 17-18l/100km if I drive like a 21 year old version of me.

Mind, I took Tek's advice on board a few weeks ago and let it warm up for the first 15 minutes (don't rev above 3000RPM and be gentle acceleration rate wise) and I'm now getting about 16l/100km driving scrappy therafter BUT bear in mind that my 50K service is due (and will be done next week)...should be good for mid 14l/100km in that kind of city driving once the service is done.

The main thing I think you should keep in mind is that you just got it and well, you have just got a new toy and if you are human it is safe to say you are playing during this honeymoon period.

Also, what fuel are you using? I think it plays a factor in things.

(sorry for the drivel gents, been drinking)

[ellie]

Thanks for all the replies.
Sean I am using premium unleaded - no particular brand. Thanks for the warm up tips . Will be doing a longer drive (about 160kms) this weekend so will be interesting to see if the average changes - if it doesn't then will have to look at whether there are other issues with the guage or tuning or something.
Appreciate all the advise from all repliers.