View Full Version : 93 petrol RR fuel economy
Darryl Prizeman
17th July 2008, 04:25 PM
Purchased the vehicle earlier this year and the fuel economy at present is about 20l/100k.
What should I expect?
mike 90 RR
17th July 2008, 04:49 PM
Purchased the vehicle earlier this year and the fuel economy at present is about 20l/100k.
What should I expect?
About that much :) Best you may get is 13 or 14
Depends .. Country or City // 5 min drive or longer??
Try to drive after the temp gauge starts to move (register) rather than start then drive .... as the EFI is sending more fuel for cold running
If you want to improve it .. you will have to start looking at the condition of exhaust / EFI / etc
aRRon
17th July 2008, 05:52 PM
Apart from the usual myriad of factors influencing fuel economy such as engine tune, tyre pressures etc I found the following two bits of technical advice very useful for my 1990 RR with Lucas 14CUX Hotwire Fuel Injection.
1. There's a recessed hex head screw on the side of the air mass sensor (aka airflow meter in the older days) which adjusts the resistance of the electronic circuit that measures airflow. If the resistance is too high = whole fuel injection system runs too rich (usual symptoms are stumbling and spluttering when cold, exhaust popping or even detonation on a trailing throttle, black exhaust smoke and sooty spark plugs). I was told that the factory setting is around 280 Ohms but that turning the screw anticlockwise reduces resistance to achieve 80 - 100 Ohms - usually necessary to get exhaust CO levels within limits. Mine was over 400 Ohms and engine running very rich. Resistance is measured across the two outermost terminals on the multipin plug that plugs in to the side of the air mass sensor with the ignition OFF (just remove the multipin plug to access the pins with your multimeter probes).
2. Original Lucas fuel injectors are commonly basket cases, especially after 160,000 km. EFI specialists say they don't come good with cleaning and resetting and soon deteriorate again. Ford "Yellow Tops" injectors will fit straight in and cost me $440 incl GST for a reconditioned set from a local EFI specialist. There's lots of posts on this site and elsewhere about substitute injectors.
These two operations did by far the most to settle my EFI problems. It's also cheap and good practice to replace the EFI Engine Temperature Sensor - about $30 to $40 and five minutes work.
cartm58
17th July 2008, 06:16 PM
my 1993 does 5km to the litre on tank average driving expect 350km tops for 65 to 70 litres refill on the tank
Psimpson7
17th July 2008, 06:31 PM
I used to get 18mpg out of my 1994 3,9 vogue se back when I was in England. Think that works out a bit better than you are getting.
I would have thought 17 or 18 l/100km would be ok.
Utemad
17th July 2008, 08:48 PM
Have a search for threads by PhilipA in regards to his oxygen sensor install. I've done it and it certainly doesn't run rich anymore. Don't know fuel figures as I run LPG most of the time.
Darryl Prizeman
4th February 2010, 05:53 PM
It has been just under 2 years since I first posted this item. Since then I have spent a reasonably amount of time and approx $2K in improving the economy of my Rangie. The best I have achieved is 13.6ltr/100k's over 500 odd K's all highway (Gympie to Rockhampton QLD) with 4 adults and our luggage. I consistently average in the low 14's for highway and high 16's around town.
What did I do:
The air flow sensor was faulty and thus replaced, improved the economy to 18/100 approx. The big saving came from fitting an adjustable fuel pressure regulator, the motor was running extremely rich. We also fitted new injectors from a Commodore, the advice I received on injectors was modern technology, better spay patern.
I am well pleased with the result.
Rangie's rule
Cheers all
Grimace
27th July 2010, 02:53 PM
I must say I only recently fitted an adjustable fuel pressure reg to my classic, and although I no longer have economy figures and the vehicle is far from standard, I did notice an improvement in fuel economy.
I done a trip to scenic rim prior to fitting the regulator, did some good wheelin, drove home, drove to work and back twice (only 3klm). Put 65 litres of fuel in (so had about 15L left).
Then I fitted the regulator, did another trip to scenic rim, drove harder tracks and more of a distance. Drove home, left the car parked out the side of the house for three days. I had 10L of fuel in the tank.
So I used more fuel on the second trip with the new regulator, BUT I put a crack in the tank about 5 minutes into the first hard track and it was leaking as fast as 3 drops a second at times. And the car sat leaking into a dirty old bucket for three days before I drained the tank :)
VladTepes
27th July 2010, 03:32 PM
My RR Classic 1994 got 17-18 l/100kms ciy cycle and a bit better on the freeway. Gawd I loved that car wish she hadn't insisted on a new car...
Anyway, when talking of old Rangies the word "economy" is used becuase the money spent on fuel is enough to run the economy of a small pacific nation.
Richard93Vogue
18th April 2011, 05:58 PM
Crikey!!! I'd better get and find out what's wrong with my 93 then.
I've been averaging 25l/100km city cycle for the last 6months or so....
The wife was standing near the exhaust pipe when I cranked the beast into life and she ended up with a trouser leg of black sooty spots, this along with the ability to run a small car on the unburnt hydrocarbons from the Rangie have sent me looking yet again for answers.
I've bought a gas injection setup to go on, not yet installed.
Oxy sensors seem to be the way to go for self tuning, so I'll have to get onto that. Can anyone recommend the cheapest way of obtaining the correct sensors?
And checking the resistance on the air flow meter will be another job to do. Along with beeuteys coil conversion, and the house renovation/extension I don't think I'll have anytime to laze about over the Easter break!
I love Rangies!!!
pibby
18th April 2011, 06:37 PM
this does the disco 3.5/3.9 so should do your engine. anyway, check with the seller. 45 pound. i just got some. postage was pretty good too, 20 pound but that included a kickdown cable too.
Lambda Sensor Discovery 3.5/3.9EFI ERR6729 Island 4x4 - Specialists in Land Rover and Range Rover Parts and accessories for all models. UK and worldwide mail order. (http://www.island-4x4.co.uk/lambda-sensor-discovery-3539efi-err6729-p-1323.html)
Richard93Vogue
18th April 2011, 08:48 PM
Thanks Pibby :)
chrisandebreg
20th April 2011, 12:44 PM
just had a play with reg's air flow meter, two outside terminals were reading 35 ohms, found the adjusting screw (mines plastic with a screwdriver slot as well as the allen head) have adjusted to 100 ohms as decsribed and will see what happens
superquag
20th April 2011, 08:56 PM
Five km/litre is 14.1 mpg = 20 l/100km
5.5 km/l = 15.6mpg = 18 l/100km
6 km/l = 17 mpg = 16.6 l/100km
I'm getting averages of between 5 and 5.5 km/litre, better on a freeway on cruise-control, and I am VERY interested to see how the bottomless pit does when I convert it to 2 wheel drive...
James in Gosnells
Bodge
22nd April 2011, 05:09 PM
We all have a go at how bad rover economy is. My 93 rangie with 265/75 16 muddies, sports exhaust and 'power/economy' chipped ECU could get 16-17 litres per 100km on highway, around 20 litres per 100km for urban driving. LPG and petrol about the same.
I now have a nissan patrol 4.2 efi petrol/lpg, exhaust, headers, gearing to suit bigger rubber. I'm happy if I get 20 litres per 100 on any run, mostly up above 25 litres per 100km for daily driving. It is not uncommon to get well above 30 litres per 100km with roof rack, loaded down with camping gear.
The rangie motor was nicer (until it died) to drive, had torque where you need it and sounded heaps cooler, plus added stability of constant 4x4.
Anyway, I never noticed how 'terrible' rangie economy was, considering the age of the car. Much better than patrol, not much worse than 4.5 petrol cruiser of same age. 16-18 litres per 100km (or better as some have stated) is really quite good for a 2t constant 4x4 petrol V8.
Cheers,
Bodge
Grumbles
22nd April 2011, 05:24 PM
I've got a 94 LSE soft dash Rangie running on 205 x 16 all terrain tyres. My average fuel consumption on 95 Octane is 14.2 litres per hundred kays at 90/100 km an hour on the twisty and hilly bitumen roads of north east Victoria. Around town and on short runs sees it climb variably to 20 to 22 litres per 100 kays. On the freeways to Melbourne it is between 12 and 13 litres per 100 km and that is at 110 kmh. I keep a detailed log book of everything including the details of each time I get fuel.
POD
29th April 2011, 09:56 PM
I find that the phrase 'Fuel Consumption' is better suited to my Range Rovers than 'Fuel Economy'.
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