NX fuel usage

[Handy Andy]

Hello Gentlemen
I'm searching for some help or guidance on behalf of a good mate who is having fuel issues at the moment.
I presently own a NW and have been part of the forum for years when I also had an NM exceed. My mate is away in the Northern Territory hence I'm asking for the help.

He is on his third Pajero (never an issue with the first two, or with mine ) the question is about his current NX . When purchased new, nearly two years ago, after a few weeks it started to use excess fuel (its a 3.2 auto) just as his previous Pajero's were (he is very familiar with how they behave). As he was away travelling at that time he was forced to return from the Kimberleys to attempt to have the problem resolved. At that time dealers in WA and NT were not very helpful so he bit the bullet and came home where a dealer on the south side of Brisbane (where it was purchased) investigated. I recall the vehicle was connected to computers and info sent direct to Mits in SA. After a week of checks etc the vehicle was back to normal doing less than 9 litres per 100klm. Two weeks ago I was with him in Brisbane and the car was doing 8.6 litres per 100 as we travelled on the M1

I have just received a call from him and he is presently in Katherine on his way back to the Kimberley's. Fuel usage is in the 12's per 100. He is trying to get to Darwin to get it to a dealer to have it checked once again. Of course if you attempt to tow anything you can nearly double these figures.

His previous Pajero's didn't use this amount of diesel towing or not towing

Can any of you learned gentlemen offer any advice or thoughts regarding excessive fuel usage in an NX. We are both starting to doubt the DPF and wonder does anyone else have any info in this regard.
My NW uses around 9 per 100 and 16 when towing but of course there is no DPF

Just searching for some thoughts at this stage. The car doesn't have 30,000 klm on it an is serviced regularly It drives perfectly does not lack power but limits his travel when away from City life
Thanks in advance Andy

[Keithyv]

You say you were with him when it was using 8.6 l/100 or so and now it is using 12? Any difference in the way the vehicle is loaded between those 2 cases? i.e. roof racks or extra gear?

Could be a difference in fuel quality too?

[DaveH]

A lot can depend on head winds. I remember my first trip. I got 12l/ 100k from Sydney to Cobar, Cobar to Wilcannia it went up to 14L/100k and from Wilcannia to Broken Hill 16L/100k. Beyond Broken Hill it went up to 18L/100k. I was panicking thinking something was seriously wrong. Then we turned right and the consumption went back to the 12's.

[Dicko1]

A lot can depend on head winds. I remember my first trip. I got 12l/ 100k from Sydney to Cobar, Cobar to Wilcannia it went up to 14L/100k and from Wilcannia to Broken Hill 16L/100k. Beyond Broken Hill it went up to 18L/100k. I was panicking thinking something was seriously wrong. Then we turned right and the consumption went back to the 12's.

I have the same issue when going from Cairns to Airlie Beach. Going down I get in the 12-13 per 100klm. Coming home 10-11 kp100. All due to headwind. Quite often you dont notice the headwind until you stop and get out of the car.

[spot01]

Firstly, I agree with above comments re load and wind, although I assume he is used to that by now.

How is he measuring the fuel consumption? Trip computer or manual records fill to fill? Over how many tanks of fuel has the consumption gone up? Has he been buying fuel in any dodgy places?

Sounds like the car is nearly at 30,000km? Is it still on it's original fuel filter?

Has he had the car serviced or oil changed during or just before the trip?

Unsure if the MY17 NX with DPF behaves like the earlier NS DPF cars where they had a tendency to fill their sumps with diesel fuel if they were unable to complete a DPF burn properly. Get him to check his oil level isn't overfull. Also, the fuel consumption of DPF cars increases when they are performing a burn.

It might be worthwhile him calling the dealer that fixed the earlier issue to find out what it was?

[oscaroo]

Here's a link on where the wind is going

Wind

[Phree_ed]

Here are some figures from a trip I have just done but I was towing a 2550kg van. I always calculate based on fill quantity and odometer distance and yeah I know the odo is probably 5% or more out but calculating for that is not worth the extra effort.

Northside Brisbane-Caboolture-Yarraman-Oakey-Miles 14.2 L/100. Car indicator 16.4
Miles-Charleville 15.6 L/100. Car indicator 15.7
Cunnamulla-St George 16.45. Car indicator 15.9
St George-Inverell 16.38. Car indicator 16.8
Inverell-Coffs Harbour 15.69 (80% van) Car indicator 14.7
Woolgoolga-Home 14.13 Car indicator 14.2

I have always found even with my previous petrol Prado that consumption on the smoother coastal highways is better than that on lumpier inland roads regardless of wind direction.

[Handy Andy]

fuel usage

Thanks fellas for your responses
I will be talking to him over the weekend before he gets to Darwin and will share your thoughts. He has a bit of extra gear with him compared to when we were in Brisbane and it was returning 8.6 ish but we had 3 in the car and golf gear then. Because he has owned three Pajeros and travelled frequently ( Cape ,Broome ,Perth , SA ,Alice and most places nearby to these ) he has experienced most condition related issues over the years. He believes its a car issue (unfortunately) and as he has been travelling he has been talking to other Pajero owners on the road and none are having the same results as he is and some are loaded up and travelling the same roads as he is. I will try and give him so help to look at this forum in case some of your replies hit the nail on the head, so thanks again.

The first time it happened he pretty much exhausted all the normal possibles ie conditions load etc. MM were able to reset his ecu and that fixed it, but here he is again. He was thinking there may have been an issue that forum members seem to get onto early however from your responses that does'nt seem to be the case

The car was serviced one month ago and is done regularly by the book, fuel filter recently changed as per MM requirements , not sure regarding where fuel has been purchased but he is carrying containers of fuel as he is not able to rely on making it to the next planned fill. He has been in regular contact with MM who have once again told him to return to Brisbane and they will investigate. His plan is to let a dealer in Darwin have a look next week as he was eventually going down the west coast to perth before coming home in October . He keeps fuel purchase records as well as uses the vehicles system
thanks boys ...I'll post the outcome in due course
Andy

[spot01]

A couple of other thoughts:
- is he still on the original tyres? (different tyres can have a significant impact on fuel use)
- has he checked for dragging brakes? (if an issue here, he should be able to notice it slowing faster when lifting off & rolling to a stop)
- is he driving any faster out there? (I noticed on a trip to the NT last year that people were generally driving faster than in other states, which would increase consumption)
- has he checked the air cleaner isn't clogged?

You say the car was serviced a month ago - I would certainly check the oil level for any increase now. When exactly did his records show the fuel usage had increased? Did it increase slowly over time or suddenly?

[littleriver]

No one has mentioned what type of fuel is he using. . Possibly the grade between stations is of a lower cetane. .

I have a feeling the fix previous was an injector relearn (sql)

...

[BruceandBobbi]

No one has mentioned what type of fuel is he using. . Possibly the grade between stations is of a lower cetane. .

I have a feeling the fix previous was an injector relearn (sql)

...

https://www2.pajeroclub.com.au/forum/showpost.php?p=585165&postcount=2

[s311_bvm]

This is timely, I have a 2017 NX GLS that I had serviced yesterday with the intent to have fuel usage investigated. The Pajero is just on 15,000 km

The only accessories I have are carpet mats, tow bar, and headlight and bonnet protectors. NO bull bars, racks, lifts, duel batteries etc. I am on the factory fit highway rubber.

Fuel consumption has been recorded at the fuel bowser, for all except 1 tank since new, from the most recent running back over the last 8 fills I have:
11.51 L/100
11.93 L/100
11.40 L/100
12.53 L/100
12.35 L/100
12.22 L/100
14.39 L/100
12.55 L/100

The Pajero is driven gently, the most common number seen on the centre display is 13.3 L/100. I have noticed that if it’s driven a bit more enthusiastically the centre display will drop to 12.7 L/100.

I am wondering if the different final drive ratio that the NX DPF cars have is leaving the torque converter unlocked for longer?

Over the 15,000 km the absolute best we have been able to get is 11.24 L/100, the worst is 15.18 L/100. To confirm we have never seen anything in the 10s or below.

We do tow a small 6x4 trailer occasionally but it’s never any more than 350 kg

At yesterday’s service they did the following for this issue:
- Performed pressure test on fuel system,
- Cleaned MAF sensor,
- Checked ECU code to ensure it was at most recent revision and it was,
- Checked air cleaner element,
- Completed a Small Quantity Learn

I will now watch to see if I can measure any improvement.

[littleriver]

https://www2.pajeroclub.com.au/forum...65&postcount=2

Sorry missed it ... although still need to know whom he filled from ..

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[flyboy]

I think you’re right about the final drive ratio maybe leaving the torque converter unlocked.

My NT with 120k will do 10.0L/100 around town in stop start traffic.

[Jimred07]

My MY17 NX has settled down. No mods, bullbars etc.

I took it back to MM who reset the fuel pump/small load distribuer and this fixed my 10's on the highway and 15's around town.

I am returing 7.3-7.5 on the highway at 100KM, this increases to 8.4 at 110KM. Around town in folowing traffic i can get under 10, but more usually 10-11.5, sounds obvious, but the more traffic lights the worst the consumption.

I am researching a tune to increrase drivabilty around town and ease the fue consumption slightly. I do 25,000/year, lots of highway, I'm happy with the highway consumption now.