Early(2007-09) Gen4 cruising performance & fuel consumption

[peterpot]

I have a 2009 Gen4 SWB 3.2 with 1140000 km that I purchased recently. I spent a lot of time finding "the right one" . I am pretty fussy when it comes to my vehicle. The guy who bought my Gen3 got a gem! I love the Gen4, it is in very good condition but I have some concerns with the performance compared to my old Gen3. We have done 4000km with it now. On pull away it is about the same as the Gen3 but when at cruising speed +- 2000 RPM the performance seems gutless / flat. It does not have that torque on the open road that my Gen3 had that would surge you forward whether towing or not. The fuel consumption is also poor at 8 to 9 km/L average. It does not surge or run uneven. It had a performance chip which I had removed. Does not smoke. I am hoping this is not normal for Gen4's. Cats shares my concern, maybe other club members?
I would appreciate input from other members. I have done the following in stages so as to be able to share and advise other owners:
Changed engine oil air filter and checked fuel filter - Genuine Mits fuel filter.
"Decatted" - found cat clean and no improvement.
Removed "windmill" from inlet - no big improvement.
Adjusted valves - no big improvement.
Blocked off EGR - no big improvement.
Checked inlet manifold - only slightly oily / clean.
Picked boost up to just under spec - a bit of improvement but still not "there".
Q1 - What would be your next check ?
Q2 - Has anyone had experience with the Suction Control Valve ? My vehicle does not surge.
Q3 - We have a Launch diagnostic device which gives you actuals while driving (boost etc) but I understand from internet comment that the ECU must be reset when fitting a new SCV. I am not sure that the Launch can reset the ECU. Any comment ?

[Nismo]

HI Peterpot

I also noticed the lack of power going from a gen3 to gen4.

I also have a 2009 model with 167k km on. My consumption in town is about 7.5km/l and open road about 9km/l @120 kmh.

I fitted a Unichip in November last year and that helped improve the lack of power but didn't improve the consumption much.

If you find a solution to this, I would very interested in what else you did.

Sent from my SM-G925F using Tapatalk

[Lock]

I'm with Nismo The Gen4 is not as peppy as the Gen3 Recently removed the Cat and that did improve performance somewhat, but still miss my old Gen3 for that rush of performance when overtaking. Low down power is the same, but highway cruising?

[peterpot]

I do not like what I believe you guys are trying to tell me. ie That the Gen4's cruising performance is inferior to the Gen3!!!!! No, no, no this is not what I wanted to hear! Oh boy - pleeeeeeease somebody comment. I hunted high and low for this vehicle and she is a beaut. You know what they say about going after / trying to date the prettiest girl ? She's probably got the most baggage!!!!

I find it hard to believe that Mits would go common rail, new turbo, etc. and put a new model on the market that uses more fuel and performs worse than its predecesor! I know they all make mistakes but it does not make sense. Let's see if some more members will comment.

Now I have noticed that the Gen4 Turbo is a lot smaller than the Gen3 I had. They both have the same boost spec. Is this maybe where the performance difference comes in? I know when turbo charging engines small turbos spool up quickly and then run out breath whereas big turbos have lag and as engine exhaust volume increases so does boost.
Now Gen3's do not suffer turbo lag so why would they go and change such a good setup?
Or do I have it wrong?
Please guys ..... I do not want to change the turbo nor do I want to chip, nor fit a high performance SCV nor a free flow exhaust. Tell me what there is wrong that we can replace and go like she should!

[peterpot]

Has anyone had their Gen4 remapped? by whom and what are your comments ?
For the "purists" they say it is like going to the phsycologist - it just gets the cars "head" right again ????!!!!!!!

[peterpot]

I have been doing a lot more in depth research on this topic. There is a lot of information out there and some club members themselves have contributed to various posts. From what I have learnt I am not keen on either chipping or remapping. I am still of the opinion that its something pretty logical. All too often I have found a simple thing was responsible.
A decision I have made is to go back and check all the basic criteria again. Rule no 1 - Check the basics first. I just have to build some test equipment to do some of the tests / checks differently.

[KurtG]

Looking forward to a simple answer Peter, thanks for the effort you are putting in here

[Nismo]

Hi Kurt,

You can maybe speak to Marius as well, he went through a lot of trouble to get better consumption on his Gen3. I am sure he will be able to give a few pointers on what to look for.

[peterpot]

When the wife and I started a guest farm a few years back, the only decent bakkie we could find was a 2.5 tdi Ford Ranger. It was in amazing condition but was an absolute dog. All the efforts to find the problem were in vain. We returned to the ratrace years later and traded it on our second Pajero. Only then to discover that there was a tiny little fuel filter in the inlet pipe of the fuel pump. And at one stage I even took the whole pump off and to a pump specialist!!!! No there is no little filter on the Pajero!

Back to Pajeros: I am quite excited as I think I might be onto something.
Cats can you give me the eighth ninth & tenth numbers in your Vin number.

[Roelf_le_Roux]

Now I'm subscribed!!