Bad Fuel Economy

[Rosco1151]

Ok, I'm after an idea of what sort of fuel economy I should be expecting out of my Nav, and also any reasons why it's currently very crap...

2000 D22 ST
3.0L Petrol V6, Manual
Steel bars up front, Tub w/canopy at rear
Completely stock.

Currently getting horrible fuel consumption... like 17 - 18L/100km...

Any ideas on what I should be getting? and why it's so high?

 

[Leprechaun]

The obvious would be too much right foot, but how is the engine? have you done a compression test, checked the plugs, state of tune etc?,

 

[Dion]

any reasons why it's currently very crap...

And the winner is...

3.0L Petrol V6

 

[Rosco1151]

Compression test no... Plugs were new a couple months back when I last changed oils/filters/etc. As for the tune, I'm no expert, but it sounds fine when running to me...

Right foot doesn't seem to have much difference between driving hard and granny-driving.

BTW, most of my driving is cruising on the highway at 100 - 110km/h.

 

[Leprechaun]

Dion seem't to think it's the your choice of propulsion?.


Good to see another Vic, You know any good tracks down your way?

Oh yeah, cool signature!!

 

[Rosco1151]

Yeah, a few people have said that as well, but I don't think that's reason enough for it to be that high...

Not really to be honest. I don't go out much, and when I do I go with mates (one of them gets all the ex-fleet 'Cruisers from his Dad's business... lucky little SOB...) So I just follow him in one of his spares...

 

[Dion]

Yeah, a few people have said that as well, but I don't think that's reason enough for it to be that high...

You're right, it's not enough for it to be that high.

Three litres of early 80's designed SOHC power does come at a price. That's probably good for 15L/100km.

As for the extra 3L/100km...

Has it always consumed this much for as long as you've owned it? Does it vary at all or is it stable on 17-18?

 

[Old.Tony]

It's a 2-ton vehicle with all the streamlining of a brick. Moving it comes at a price. With petrol, that price is a little higher. I think the fuel consumption increase for petrols is higher than with diesels as the vehicle's weight climbs.

I'm not convinced adding ethanol to fuel (which they now do, at least in NSW - 10%) is going to provide the same economy as straight dinosaur. NRMA did a study on the 3 different unleaded variants and determined that the savings per tank using ethanol blends were more than offset by the higher consumption rate, making the ethanol blend less economical (for the driver). This does of course make it more economical for the fuel company and for the government, so naturally with $ to be had, they both would have cut off their collective left nuts to make it happen.

 

[Dave]

Id say the bullbar wouldn't help.

Bigger tyres ?

Dave.

 

[Leprechaun]

My old commodore V6 powered Hilux got 20-25 L/100k's, the killer was the 4.88 diff.

What rev's do you cruise at?

 

[Dave]

VG30E powered D22's run 4.375 like the ZD30DDT powered Nav's.

Its probably reving less then a VG33E powered D22 as they run 4.636 gears.

Dave.

 

[d40 abuser]

put a gen 3 in it

 

[scottybobcat]

Thats the shit but dont expect better fuel ecconomy.It will pull like a 12 year old boy or pull a bend out of the highway though.lol
It may need a timing belt done on it if you are lagging power which wil chew up the fuel

 

[Old.Tony]

08Kingcab has hit a good point there.

In the diesels - and I don't see why the petrols should be a lot different - the "sweet spot" for economy is in top gear just at the point where the torque comes on strong, and for a stock engine (no chip etc) that's about 2,000rpm - which equates to about 95km/h.

Does anyone know what RPM the sweet spot in that model is? That'd be the goal, to get the revs there and let the old girl do her thing.

 

[Rosco1151]

Dion - Yeah, I think it's been about that since I got it, (just before New Years), but I've only been paying close attention and keeping an eye on it the last few months.
It stays pretty much the same unless it's loaded up with mates and camping gear, towing a trailer with stuff going to the tip etc. Higher consumption then for obvious reasons.


Old.Tony - Interesting point about the 10% ethanol fuels. I've been using E10, I might try running a few tanks of normal through it and see if it's any different.


08KINGCAB - Cruising RPM in 5th gear @ 100km/h is a little bit over 2600.