1HD-T Fuel Economy

[vSAHARAx]

What sort of economy are you lot getting out of your 1HD-T?

Mine is crap!!!!! 17.4L/100 city running, only gave it a foot full once! rest of the time driving it nice and steady. Same fuel pump, Stopped filling after one click. She took 50.1L over 288k's. I cant figure it out!!!!

[Sic Lux]

Fark dude don't sound right

[mud4b]

sure doesnt.

i usually get around 1100 ks to both tanks no matter what sort of driving i do.

[dow50r]

If its running ok, then its leaking it somewhere...10-14l/100

[spongerx]

Dirty air/fuel filters? Due for an oil change?
The mileage on my 3L always goes to crap when it's close to the 5000k service interval but not quite that bad. Gotta change air and fuel filters every 10,000ks over here thx to the craptastic fuel we get and a lot of dust on the roads too.

[lshobie]

Change the fuel filter and air filter, check your idle rpm with the factory manual to make sure it is in spec.

Do you have an auto or manual - if it is an auto - make sure it is changing gears at the right time and not lugging.

Does it blow black smoke on startup - at idle, at acceleration - and/or at cruise?

How many kms on it, have the injectors been cleaned? is the pump timing set correctly?

Is the truck sluggish - or does it have lots of power?

Any leaks around the injection pump?

Any kids stealing your fuel?

[dow50r]

I agree with everything said above...start with fuel filter and air filter.
The other things worth mentioning...did u get full litres at that pump?? Is this the first time you have checked or is the usage repeating itself....
Also....IF...you were filling the sub tank, and the main was not full....the diverter is designed to fill both when filling subtank....gets people all the time...

[trains]

Have you checked for air in your fuel system.
Ive been surprised at how much of a difference that this can make in performance, and economy.

Trains

Ps, what fuel are you running??

[vSAHARAx]

Ok heres the basics,

I have owned it for a month Its done 320 000k, and its a 5 speed manual

Last week it recorded around 15L/100 i fill it up everytuesday night reguardless of how full it is, have been using Freedom fuels.

Motor has been rebuilt, my mechanic is guessing by the condition the big end bearings, the crank didnt have a mark on it and it has aftermarket conrod bolts.

The injector pump had all new seals put in around 3 months ago apparently and the injectors were also supposed to be done.

Its running a K&N Air filter which i took out of my old truck and fitted to this one was cleaned around 7000k ago

Idles around 750rpm when warm, at around 700 when cold, smokes a tiny tiny bit when cold at idle. lets off a puff of smoke on take off and Smokes a fair bit when you get up it, Cruising it doesnt blow smoke (all black smoke)

Wouldnt say its a slug and wouldnt say its a power house She goes well, doesnt go as hard as mums car hers is also a 91 1hdt, will do a economy check on that next fill.

***Had a look and noticed it is leaking around the bottom of the pump, not badly though*** will get it looked at asap

it has roughly 4.5" lift and 305 (33") muddies.

[Frankenyota]

Hey mate did you have your mechanic pull the sump and check the bottom end after you brought the truck.

280km out of 50l is what my vn v6 auto with 35" tyres gets,
not so good.

Matt

[vSAHARAx]

Hey mate did you have your mechanic pull the sump and check the bottom end after you brought the truck.

Matt

Sure did, booked it in straight away for my mechanic to change the big ends, he was rather impressed with the state of the bottom end

[dumbdunce]

first thing you need to do, in a hurry, is get rid of the K & N and install a fractory fibre filter. search if you don't understand why.

14 - 15l/100km is not really that far off the mark for a 1HD-T 80 - it is on the high end but you did say it was all city driving.

if the fuel pump was removed for the repairs it may be mistimed, you will need to refer it to a specialist to have the timing checked and corrected.

it will also pay to have EGT and boost gauges installed, then aim for peak boost around 9psi and peak EGT's around 550 - 575C post turbo for peak efficiency. you can get more power with more boost and more fuel but for peak efficiency those are good numbers.

also check all the basic stuff; are your brakes dragging/wheel bearings sloppy/wheel alignment good/tyre pressures good (at least 35psi on the road), do you have stupid power robbing accessories like a snorkel, does it still have the facrtory exhaust and if so is it clogged full of soot, if that's all good then have a look at your turbo, are the compressor blades fragged, does it have excessive axial or radial play, is the inlet full of blowby oil, are you running too thick oil, does your gearbox, transfer, diff have 120W oil in it to keep it quiet for a quick sale, all these things will contribute to fuel economy but the biggest influence is obviously your driving habits.

my 1HD-FT 80 with 35's, 5" lift, all barwork, rear tyre carrier, winch, is my daily driver and regularly returns 12l/100km day in, day out. I don't drive it hard constantly but it does cop the boot more than once every day. the aerodynamics of this vehicle are so fantastic that at highway speeds the economy gets worse only 'driveline' modifications are 2.5" mandrel bent straight through exhaust, pump tweaks, and 15psi peak boost.

cheers

DD

[vSAHARAx]

Ok K&N is out, standard filter back in.

It is leaking externally from somewhere (not badly, but its weeping) will go to Highway diesel or who ever tomorrow arvo,

do you put EGT Pyro on the exhaust manifold or turbo dump pipe???

Brakes, Check
wheel bearings - cheack
Wheel alignment done, drives great
tyre pressure 36psi cold all round
No snorkel (yet)
Turbo seems fine
gearbox etc all good.
Driving style, drive it nice most of the time (accelarating normally, changing gears at around 2200rpm-2400rpm, Only up it once in a blue moon.

My bet is injector pump and injectors will let yas know

Thanks heaps dumb dunce your a champion!!!

[Tapage]

do you put EGT Pyro on the exhaust manifold or turbo dump pipe???

I would choose exhaust manifold for more accuare readings .. and ususaly set my tires to 30 PSI at cold ..