sorry I meant opal petrol

RMD, no distributor on a 4.8. Electronically controlled.

thanks for taking the time to reply

cheers thanks for the reply

Wow, 21 L/100 normally is only a little better than a 22 ton diesel coach I used to drive. 45l/100 is way worse than the coach. I wouldn't be able to afford the fuel costs for any outback trip.

Hmmm well you can't change the tuning on a 100 series v8 petrol ..
Toyota service department told me (in 2016) to use BP 98 & you will notice the difference.. at that stage i could agree .

Woodsy
If a 4.8 normally runs on 91 and timed to do so then all ok. With the "Outback Experience" of using Opal which is said to be also 91 or better, the fuel which you received may have been stored for a while and much of the most volatile molecules had left the scene through evaporation in Aussie heat. That leaves lower volatile fractions of fuel to make up the fluid fuel you received. When used, MORE fuel has to be injected to make up the energy/power required to drive the vehicle forward. That may explain why very high fuel use. If there was any contamination in the fuel the OXY sensor may have received a blast of rubbish and not sensed OXYGEN levels very well. Most times they then cause the ECU to overfuel until the sensor is replaced or the crap is burnt off the sensor by long hot running. Just a thought.

Might also explain why some of the community folk think they have enough fuel to travel to see mates and find they run out somewhere and search parties then become involved.

If fuel has deteriorated through evaporation the fuel burning rate will be slower when ignited by the plug. That means the fuel is still burning when leaving the the cylinder, a bit like late spark timing, and so causes overheating and engine failures if extreme or driven hard while it is happening. Burns exhaust valves!

Any fuel which is still burning upon exit from cylinder is total lost fuel efficiency as that portion contributes nothing to gas expansion in the cylinder to push pistons. If the burn hasn't happened by 2/3 of downward piston travel, then in the last 1/3 or beyond nothing much is gained. All fuel should be burnt before exhaust valve opens. Best if it is!

Bazooka
When only OPAL is allowed out there, an owner cannot fill with a higher RON fuel because it isn't available.
Why? Sniff Sniff.

No kidding RMD. Not much call for swimming coaches for fish but if I come across a vacancy I'll let you know.

G,day Zippo.
" I'm anal about keeping accurate fuel usage" May you someday, as I did after many years, reach the state of Nirvana re this problem. This consists of filling the tank and just driving off into the sunset. :)
Dave.

Hahaha...I did exactly that for several years. Then I relised what a complete waste of time and effort. Now I couldnt care less about price or mileage. If the car needs diesel I just pull in and fill it up..

I only do this while touring around remote country, not in the burbs. It serves to allow sensible range projection (and avoiding troubles) as well as warning of anything untoward in the engine behaviour. About of a third of that running was/is on Opal.

Elsewhere I do as you guys do, just fill and drive.

> About of a third of that running was/is on Opal.

And no engine destroyed Zippo? Amazing how myths can live on in this day and age of 'fingertip info'.

Nah, still running on the same engine after four past trips around "Opal territory". Currently in Alice and heading back via GCR next week. [Maybe this trip Scotty will be right - "she's gonna blow, Captain".]