'04 TD Auto poor economy

[JDWhite Lurker Find all posts View Profile Close JDWhite]

Hi Guys,
Long time lurker, first time poster.....

Had a read through a few of the fuel consumption threads and really couldn't find what I am looking for as far as an answer goes, so I was wondering if anyone has had the same issue with a suggestion for a fix.

Had the Prado for a few months now, when I bought it I drove it from Mackay to Brisbane to get it freighted to Adelaide and the fuel economy was 10.9L/100km. About what I expected.
Problem is, it just seems to be getting worse. Firstly, its the family car, Missus drives it to drop the kids off at day care, supermarket and all that, usually fairly short trips around town. Not ideal for economy I know.
Filled it up tonight at just under 900km on the trip meter and it took 144L, somewhere around the 16l/100 mark.
I have a set of BFG tyres on it which are 265/70 (I think, too dark to check now) which I know has thrown my speedo out according to my GPS. Even with the almost 10% difference (100km indicated is 108 on the sat nav) its still very thirsty from what I read others are getting here on the forum.
Planning on getting a service done next week, the air filter looks not too bad, oil same.
I was thinking about getting it in to MTQ in Adelaide for a look, but if I can avoid them charging me to give me the answer to a common problem I will.

Anyone got any thoughts?

Cheers,
JD

[baggs71 Inactive member. Find all posts View Profile Close baggs71]

This is what I do and I'm averaging 12.4-13.6L per 100...around 1250-1290 per fill.

1. Install unifilter
2. Use a fuel injector treatment one every 40k

Thats all I do....im about to rip off the intercooler and manifold and give them a good clean then install a catch can...

That to my limited knowledge....do the cheap fixs first...then if that does not work then check back here and ask more questions....

Or your wife has a lead foot...

[baggs71 Inactive member. Find all posts View Profile Close baggs71]

Dbl post bugger

[nigelh Member Find all posts View Profile Close nigelh]

Yeah I think 10.9 is too good for a 1kz. U must of had a tail breeze. Mine does the same as baggs. 12-14 lt per hundred.

[mackayvx Advanced Member Find all posts View Profile Close mackayvx]

Gday JD.
You bought the beast in Mackay eh?
Well 11ltrs would be a dream for me but 16 would be a fair economy when im fully loaded towing the camper.
Mind you my beast spiked at 22ltrs/100kms with a cracked head returning from Cape York last year.
This is how tuff these 1kzte motors are... I knew something was seriously wrong with the prado up the cape.
I lost heaps of power and it was skulling fuel. I know my way around a vehicle and it had no symptoms otherwise of a major failure.
It didnt over heat, didnt use oil, no milkshake in the oil and no oil in the coolant.
I thought the turbo had failed but it was still spooling up.
Anyways a whole 8 weeks later and about 6 mechanics later i diagnosed it myself.
My radiator was holding pressure overnight. In the morning my hoses were hard and the when releasing the cap it blew off pressure.
It should not do that! The crack was letting compreddion inyo a water jacket in the head and therefore pressurised the radiator.
I dont want to scare ya but other than you air filter, vacuum leak or a change in ypur cars carachteristics like mods...
Ie tyres, bullbar, roofracks you shouldnt really have youe fuel consumption jump.

Are you sure 10.9ltrs was correct?
If so, call the guinness book of records cos thats a record that you will hold forever.

Drew.

[baggs71 Inactive member. Find all posts View Profile Close baggs71]

Guiness world record hahahahha funny stuff...
But it is true...a lot of KZ owners hint at outstanding fuel economy. ...my guess its a almost cleanskin (mod less) truck doing country klm with cyclone tracey tapping on the rear window. Hhehehehe eheheheheh.

Ive recently unloaded the truck for 4 days for maintinence and was surprised how quick to get up to speed it was...but thats like false economy as we all load the bugger out of them on the outback trips...and thats the fuel economy figure we want...not best case scenario....

[matt150 Avid PP Poster! Find all posts View Profile Close matt150]

Mate the best cruise run I have ever got out of my modified 150 series is 10.6 litres per hundred. Towing my camper empty is 11.4 litres per hundred. I'm not sure if ya initial figures of 10.9 out of a 1KZ 120 are on the money..

[zutta Senior Member Find all posts View Profile Close zutta]

Im the same as Baggs here. anywhere from 1250-1350 tank depending on driving and where with what on the back with 7x5 box trailer loaded recently moving i was high end of 13's. unloaded highway travel sitting on 90-100 is the sweet spot for my prado i get low 12's, if i bang it on cruise to 120 on the dual lanes i notice the consumption difference. like any car though they all have their sweet spot.

[JDWhite Lurker Find all posts View Profile Close JDWhite]

The 10.9 was correct, however I factored in the tyres being out by using the distance travelled on the GPS rather than the trip meter. I was empty, std car, no roof racks/rails etc. Sat on 100 on the GPS, showing between 90-95 on the Speedo.
Even though, the economy I am getting is still rubbish around town, my Territory was getting better than this, and by quite a bit!
Please keep suggestions coming, otherwise I am off to mtq to deposit a few hundred dollars their way.
JD

[baggs71 Inactive member. Find all posts View Profile Close baggs71]

If the fault is not obvious in that you still a burning through upwards of 19L of fuel per 100klm driven...and its unloaded??? Then you may have a big problem....im hoping one of the pagan forum gods will enter the discussion today and give an indication on where to look....head gasket? ....

[Guest Close Guest]

How short is a short trip and do you live in the hills?

A mate with a Camry V6 used to live in Hope Valley. He had a steep driveway and the first road out of his street was steep too. He got 16L/100km.

Now he has moved to Wynn Vale and the slopes are more gentle. He now gets 12L/100km.

Could it be where you live?

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

IMO 10.9 is super duper for a 1kz auto.
Tailwind, no mods, no load, nice right foot, stay under 100k then maybe.
About the best you get is 12.
It can often be 12-14 depending on mods and load.
But doing those short trips won't help.
I think there could be a lead foot and all short trips.
How many klms?
Try getting your injectors rebuilt.

[JDWhite Lurker Find all posts View Profile Close JDWhite]

Different circumstances re the good and bad economy. Around town is my issue, maybe it is the lead foot thing, I probably should let her drive me around a few times whilst saying nothing to check!
If I could get it to 12-13 around town I figure that is probably not too far off the mark. I have been driving it the last week or so, again, short trips, maybe I should top it up and check my driving? Probably done 120-140km by now.
To be honest I thought it may be a common problem and a common fix, like injectors or something. Maybe I will drive around tomorrow and fill it at the end of the day and see what happens.
Mate with a 90 series TD said the injectors are quite cheap new A/M, something like $500 set?

Out of interest, tyre pressures on the BFG's? What are you guys running?
JD

Live at Richmond, so pretty flat around here. Appreciating the feedback, thanks and keep it coming.

[Bushbasher Out of control poster! Find all posts View Profile Close Bushbasher]

The BFGs 265/70 will make the speedo accurate however the odometer may not read 100% accurately. I have odo reading 412km but scanguage shows 432km. The speedo has been checked against an on-board Falcon HR Mobile Radar and reads exactly the same as radar and scanguage from 60 through to 110km/hr. The difference would not make a huge difference to the economy readout so I would suggest you have other performance issues. Certainly furious acceleration and heavy braking in a metropolitan/city environment do not bade well for economy. I've managed 9.5 for the 400 odd km around town by just moving smoothly. We have lots of roundabouts so there isn't much stop/start driving for me.

[baggs71 Inactive member. Find all posts View Profile Close baggs71]

Im gunna suggest another thing if I may....

Fill it....drive it until second tank lights up.
Place 300ml of deisel fuel injector cleaner treatment.
Drive till almost empty (once empty light comes on drive another 40klm)
Fill again...Drive...
Fill again...drive...

Then tell us what fuel you have used...
Do not panic.

Forget driving around town as a problem....im thinking someone has a bad lead foot or worse...you have a major problem on your hands....

Three tanks drive...1st sub tank with trewtment only once....then tell us what happened....
Talk to you in 6-9 weeks