02 D22 Overfueling? Why?

Hey all I have a 2002 D22 Navara ST-R. Now it has 168,000km and I have only had it for a couple of months.

Im pretty sure when I bought it I was getting close too or just over 700km per tank.

The only mod iI have dont engine wise is a Genuine Nissan Snorkel.

Now I just filled up and it took 67 litres of Diesel and i got 520km out of that.

So in theory;

67 / 520 = 0.128846

so then

0.128846 x 100 = 12.8L per 100km's

This is not right is it?

What could be wrong that my Nav is using so much fuel?

It cant be the soley the snorkel could it?

Any ideas would be much appreciated..

Damien

If it's not blowing clouds of smoke, I'd let it have another couple of tankfuls before I jumped to any conclusions about it.

Variations in load, driving methods, fuel quality and more can affect the consumption rate. At 168,000km, your vehicle ought to be doing very well economy-wise.

We expect to get around 12.2 with ours (due to the weight of the vehicle), and we're pleasantly surprised when we get 11s or better.

Things that I do, to ensure better economy:

1) Don't push the car to take off hard. It's a diesel, it'll get there. Moving 2T+ is not easy and this is one area that consumes a large amount of fuel.

2) Buy big-name-brand fuel ONLY. And for that I generally only use Shell. Shell don't add bio to their fuel, and I've had (mostly, with the exception being Shell Wilcannia NSW) very good performance from the fuel.

3) Buy fuel from service stations with moderate-to-high turnover. Truck stops are good. Fresh diesel performs better than old diesel, which may begin to form waxy deposits.

There might be some value in having someone drive your car away from you at moderate acceleration so you can watch the exhaust. Clouds of black would indicate possible injector wear, or an air intake restriction like a dirty filter.

Your snorkel is a *minor* restriction but any of the big-brand units should not affect the fuel consumption that greatly. My snorkel's an Airtec (Nissan-branded), but the Safari should perform fairly similar.

Thanks Tony, thats some great info...

Just some more info, I do have a Ironman Steel bullbar with winch, ARB canopy on it with ARB Roof Racks, It is Lifted 2" and also has 31" Maxxis Muddies on the car.

So this consumption might just be normal yeah then?

Check your consumption with the D22 ones in this thread.

http://www.navara.asia/showthread.php?t=83

Larger diameter tyres will always increase fuel usage unless you change your diff ratios, and even then there'll still be issues like rolling resistance that you just can't overcome.

The issue is the force (leverage) that the engine normally applies to what is essentially a larger lever - the larger diameter wheel. Longer lever = more force = more fuel.

With steel bar, winch, canopy and the bigger tyres, I'd say you're not doing badly at all getting 12.8 LPHK. You might be able to improve it, but overall that's not too bad considering what you're asking the engine to pull around.

Hmmmmmm, could be the reason's I posted on 4wdmonthly on the thread you posted in the Navara section.

Dave.