Thirsty NP 2004 exceed 3.8i

[Geoffro68]

Gday all,I'm new to all this so take it easy on me lol.
Got myself a late 2004 NP exceed 3.8i,178,000ks.It was doing 25lts per 100ks around town.I have had it dino tuned,replaced plugs with twin tip iridium plugs,KN air filter,O2 sensor,small manifold leak fixed.Now its running at 20ltrs per 100ks.Just wondering if there is anything else I can try so I can get this down to the 15lts to a 100ks that it is supposed to be running at.
Any advise would be appreciated. Also I had its first ever transmission service since it was new.
Thanks.

[benckj]

they are thirsty beasts around town. Should drop to around 12l/100km when on the open road.

The only other suggestions for economy gains is tyres & exhaust. Can be quite $$ for little gains.

[erad]

You say "around town". Presumably this means short runs, in traffic. Yes - they are thirsty in these conditions. Is the engine getting up to proper operating temperature? If it is running too cold, it will use lots more fuel. Tyre pressures too low can also cause extra drag (increases fuel usage)

[Geoffro68]

Air pressure in tyres are at 40,temperature gauge runs halfway between quarter and half.I'll have to go for a good highway run and maybe a few cobwebs might clear somewhere.

[disco stu]

Maybe stupid question, but did you reset the ecu after all the changes you made?