Fuel Consumption Again

[grahamnaismith]

OK I know fuel consumption has been done to death but this a specific 100 series question.

2001 4.2 Litre TDA Amazon HDJ100

China 2008 - New BFG All Terrains. Patriot Roofrack with reasonably chunky Roofbox and fully fully laden including 40 litres of water, 40 litres of fuel in Jerry Cans, tools, medicine, books, food, cooking stuff and 3 adults (inc. Chinese guide) + 3 kids. Crap (but very cheap!) Chinese fuel. Cheap chinese fuel filter. Temperature + 30 degrees. Aircon on, radio on, invertor charging kids ipods etc. Altitudes of +11,000 feet and -900 feet. 70-80mph on good straight roads but never put foot flat on the floor/hard accelerating. Long long drives. Tyre Pressure approx 34 psi. Very hilly. Approx 15-16 mpg.

UK 2011 - Same but not so bumpy BFG All Terrains. Patriot Roofrack with no roofbox. Car empty. 1 Adult. Posh expensive Shell fuel. New Toyota fuel filter, Toyota oil filter/oil change to expensive synthetic oil, new toyota air filter & diesel additive. Temperature 5-15 degrees. No aircon on, radio off, no charging Altitudes of 0 feet to 800 feet. 70-80mph on good straight roads but never put foot flat on the floor/hard accelerating. Steinbauer P-box chip installed on default settings to assist with fuel economy. Injectors all done. Tyre Pressure approx 34 psi. Pretty bloody flat. Approx 16-17mpg.

Come on everyone - throw your tuppenth worth in. I'll try anything - even driving with the wing mirrors tucked in.

 

[Graham]

OK I know fuel consumption has been done to death but this a specific 100 series question.

2001 4.2 Litre TDA Amazon HDJ100

China 2008 - New BFG All Terrains. Patriot Roofrack with reasonably chunky Roofbox and fully fully laden including 40 litres of water, 40 litres of fuel in Jerry Cans, tools, medicine, books, food, cooking stuff and 3 adults (inc. Chinese guide) + 3 kids. Crap (but very cheap!) Chinese fuel. Cheap chinese fuel filter. Temperature + 30 degrees. Aircon on, radio on, invertor charging kids ipods etc. Altitudes of +11,000 feet and -900 feet. 70-80mph on good straight roads but never put foot flat on the floor/hard accelerating. Long long drives. Tyre Pressure approx 34 psi. Very hilly. Approx 15-16 mpg.
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Graham said = Maybe the 15 - 16 mpg isn't so bad in this situation.

UK 2011 - Same but not so bumpy BFG All Terrains. Patriot Roofrack with no roofbox. Car empty. 1 Adult. Posh expensive Shell fuel. New Toyota fuel filter, Toyota oil filter/oil change to expensive synthetic oil, new toyota air filter & diesel additive. Temperature 5-15 degrees. No aircon on, radio off, no charging Altitudes of 0 feet to 800 feet. 70-80mph on good straight roads but never put foot flat on the floor/hard accelerating. Steinbauer P-box chip installed on default settings to assist with fuel economy. Injectors all done. Tyre Pressure approx 34 psi. Pretty bloody flat. Approx 16-17mpg.
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Graham said = Maybe the 16 - 17 mpg is quite bad I would have thought.

Come on everyone - throw your tuppenth worth in. I'll try anything - even driving with the wing mirrors tucked in.

.
You seem to have had a fair heavy load in China, and the fact you mention the poor quality fuel.
Is the posh expensive Shell fuel of any benefit to an older truck, I thought it was only of any small significant improvement to the newer common rail engines.

Maybe the "poorer " quality fuel in China was just a feeling, due to the altitude?
It sounds like your truck engine in China was really working hard with the huge weight lugging around, sounds like you were loaded well up to the max.
Where as, driving in the UK, looks like your truck engine was doing significantly less work, but using more fuel.
What to suggest, ? will the 100 series benefit from driving slower.
It does sound strange though, and in these times we all need the bost miles out of the precious "black gold"


Graham

 

[fridayman]

Try 2 psi more and see if it helps. I am also on a mini quest for more mpg on my 95 and tyre pressures are making a difference.

 

[Jon Wildsmith]

Easing off the go pedal might be your only hope

 

[Julian Voelcker]

Have you tried turning up the chip - whilst providing more power and torque making things more effortless it should be increasing the efficiency of the engine.

I would be tempted to try it for a tank full - turn it up a little bit at a time (around 1/8th of a turn at a time) until you start to see smoke on hard acceleration (a local steep hill is useful for testing this) and then back off one notch.

Hey, at least it should perk up the drive a bit

 

[Dave Docwra]

62mph max speed will give you a much better fuel return..