1hd-t auto, ridiculous fuel economy... 30l/100km (1 Viewer)

[toyo80]

1hd-t auto, terrible fuel economy,
my mate just did under 300km on full tank ~90l we are out of ideas
-engine operates smoothly and normal
-he has narrow 33x10.5 tires
-his pump was recently timed from around 1.65mm to around 1.3mm (its pretty near casting marks on the pump and flange)
(he even says it might be worse after timing)
-doesnt soot pretty much at all
-compensator was tuned
-stock turbo pusching under 14psi
-short freeflowing exhaust
-normal snorkel
-all brakes were done and are good
-Lockup in converter works
-his compared to any other auto 1hd-t 80 even tuned feels a bit gutless
-no restrictions fuelwise
-no leaks, no smells, no funny sounds, all pretty normal
-did i mention no soot?
-temps seem all right, its not hot under the hood, no egt gauge though
-we tried to hook small electric fuel pump up, but nothing changed
-Anchor all the way up
-my similary tuned and speced 80 with more fuel and soot needs 12l/100km tops

 

[GTSSportCoupe]

Maybe don't trust the trip meter? Consider using a gps instead?

Any fuel leaks anywhere?

 

[toyo80]

Maybe don't trust the trip meter? Consider using a gps instead?

Any fuel leaks anywhere?

he checked trip meter with gps, under 7% difference, nothing major, and come on, even if this was 400km on full tank its still pathetic mileage.

no fuel leaks as mentioned, on one trip on the pavement it just uses whole tank, he has garage so nobody steals the fuel also

 

[FJBen]

When is the last time the injectors were cleaned/tested?

Possible bad spray pattern
Weakened springs causing too early and longer fueling,
By retarding the timing you are effectively giving up more power/efficiency which would explain him saying it's gotten worse after timing.

I'd go to there next if you have already tested brakes and the like. Sounds like lower power, higher consumption...signs of injector issues. Find a place to test and clean injectors and then time it again.