X5 F15 BSR tuning 40d fuel efficiency

[5Xdrive]

Have anybody tried tuning on your 40d engine?
And did you get better fuel efficiency
My engine runs 12 km/l in eco-pro with an egg under the shoe
BMW says 16,7 km/l ???

Any comments ?

[W37V]

No direct experience to your question and can't speak of 40d, but in US we have 35d which is equivalent to EU 30d. All engines are variation of N57.

On my stock 35d, the best I got was over 41mpg (US) or 17.5 km/l. My average during regular commute is about 33mpg (14km/l) and with light traffic about 36mpg (15.3km/l).

Which leads me to ask: Is your car running OK? Any shadow codes?

Putting a performance tune on this car will be a catch 22 with fuel economy. Under light (partial) throttle application, you will actually use less fuel, while under heavy use, you will use more - duh. First few weeks with new tune you will actually get worse economy as you will be pushing the car a bit more then usual to enjoy the new power.

The reason why partial throttle application generally yields better fuel economy is because you have to hold the pedal for shorter duration to achieve your goal (accelerate, pass, etc.) thus more time cruising at lower rpm.

However, there might be tuners out there who can build "fuel efficient" tunes which are specifically made to maximize fuel economy by potentially reducing power, making throttle lazier etc. Think of it as eco pro ++ mode.

https://www.racechip.us/fuel-economy.html

[5Xdrive]

Originally Posted by W37V

No direct experience to your question and can't speak of 40d, but in US we have 35d which is equivalent to EU 30d. All engines are variation of N57.

On my stock 35d, the best I got was over 41mpg (US) or 17.5 km/l. My average during regular commute is about 33mpg (14km/l) and with light traffic about 36mpg (15.3km/l).

Which leads me to ask: Is your car running OK? Any shadow codes?

Putting a performance tune on this car will be a catch 22 with fuel economy. Under light (partial) throttle application, you will actually use less fuel, while under heavy use, you will use more - duh. First few weeks with new tune you will actually get worse economy as you will be pushing the car a bit more then usual to enjoy the new power.

The reason why partial throttle application generally yields better fuel economy is because you have to hold the pedal for shorter duration to achieve your goal (accelerate, pass, etc.) thus more time cruising at lower rpm.

However, there might be tuners out there who can build "fuel efficient" tunes which are specifically made to maximize fuel economy by potentially reducing power, making throttle lazier etc. Think of it as eco pro ++ mode.

https://www.racechip.us/fuel-economy.html

I just wrote a long reply and the app went offline 🎃🎃🎃🎃

[5Xdrive]

I think I have to test a chip

My 520d F11 ran 14,7 km/l with chip
Maybe I'm no good at saving fuel 😄

I drive som queue in the day. I drive around 100 - 225 km/day
queue, motorway and big city's
Maybe 12 km/l is not that bad!?

[CHECKERED]

Originally Posted by 5Xdrive

Have anybody tried tuning on your 40d engine?
And did you get better fuel efficiency
My engine runs 12 km/l in eco-pro with an egg under the shoe
BMW says 16,7 km/l ???

Any comments ?

are you using premium diesel or regular?
do you add any additives to the fuel?
how many miles on the car?
What oil weight are you using?

on my 35d i'm getting around 34mpg (6.9L/100km) on highway and 28mpg (8.4l/100km) in town

I just installed a CPA tune and will report back to any changes

[5Xdrive]

I'm using regular diesel
The car has run 70.000 km
I think that's 43000 miles
Oil is 5w40
No additive to fuel

[CHECKERED]

Originally Posted by 5Xdrive

I'm using regular diesel
The car has run 70.000 km
I think that's 43000 miles
Oil is 5w40
No additive to fuel

1. the car will need carbon cleaning in the intake manifold and intake valves
2. the oil you should be running is 0w-30, and for best mpg 0w-20 (but you might consume a bit of oil with this low viscosity)
3. you should be running a lubrication additive, some additives are very high concentration so you wont need to add much per tank.

here are the resources post #9
https://www.ford-trucks.com/forums/1...-additive.html

[5Xdrive]

Thanks for the advice!
I have today bought 20 liters 0w30 oil
Addictive for the fuel and talked with BMW

They say I need to bring the car in for a check the AGR. Valve might be faulty if it leaks cooling water "engine might burst in flames"
All on bmws account.

BMW says: The car can run 16,7 km/l if the car is taped up and done a lot of extra fixes.
But after new standards the car can't be fixed and taped so the fuel efficiency in the commercials is now very different.
If you look at the picture a car like mine runs 13 km/l model 2019 (new more efficient engine)
So my 11-12 km/l might not be that bad!🤨

[LauriJ]

I have the same problem with my 40d.
The mileage seems a bit high. I previously had a F15 30d and the best mileage that i could achieve was 5,4L/100km (43,5mpg). But the best that i could do on the same road with 40d is 6,5L/100kg (36,7mpg). More than 20% difference! I also have a Toyota Land Cruiser 3.0. Its know to be not that economical car and i can achieve 6,5L/100km on the same road. So BMW should have much better mileage.
BMW technician has done all the checks that are possible, EGR, Intake, DPF, thermostat, brakes, wheel alignment, bearings etc. Dealership says everything is fine.

I have also compared to exactli the same spec 40d (drove myself the same road back to back with both cars). And the other 40d had noticeable difference in consumption (about a 1litre/100km).

I actually don't mind about the consumption so much. But i am constantly thinking, that maybe the engine isn't burning fuel as cleanly as it should and all the carbon builds up in DPF and then it has to burn it self clean again...and it has to do this process a lot often than normal. And then a have to replace DPF filter sooner. Hope you get my point.
I have also noticed that every time i come from driving, i hear cracking sounds coming from under the car - just like the exhaust is very hot and it cools down. With other cars i haven't had this.
This is also a sign from unburnt fuel (EGR temps get to high). But i don't know what to do with this.

I have only one more idea, to take intake off and check if intake ports are clean (i know that 30000km ago dealership cleaned intake manifold but maybe they didn't clean intake ports).

[5Xdrive]

LauriJ - i have a BMW service shop to test my var for coolant leaks the 23/4 they will take an camara in to the egr cooler at test the egr valve

I believe they will say if they see a problem with carbon buildup in the intake

I will try chip tuning after this to see the fuel economy raise up

I will get back to you
Chers

[JensM]

Hi 5Xdrive - Im also Danish but currently living just south of border (Flensburg).
Currently running an X4 30D with Racechip - According to Racechip should have around 310HP/675Nm - decent fast :-). Car so far done 117.000 km whereof approx. 110.000 with chip and with no problems - btw going to trade in for new X4 40D. We are driving 40.000km a year and day to day 140KM, always using premium diesel and believe clean for any sod. Average consumption is 6,7L/100 km and this includes 3 yearly trips to south europe with heavy foot. On daily driving to job doing around 6L/100km. I have checked so many times when filling up - actual consumption match computer within 2-3%. Before this we had an 2012 X3 30D Msport also with Racechip - this was doing an average of 8,5L/KM.

You will see a slight improvement in fuel economi with a chip but as other said, not in the beginning until you get used to the impressive power increase. But with normal and within speed limits (quite costy in Denmark) you will see an inprovement. However I do not see 12km/L (8,3L/100km) as way off. Good luck /JensM

NB: if going with a chip I can give best recommendation to RAceChip. We are on our 3rd....Decent price, fuel friendly, easy to install and take of when service and very good power increase

[CHECKERED]

Originally Posted by CHECKERED

on my 35d i'm getting around 34mpg (6.9L/100km) on highway and 28mpg (8.4l/100km) in town

I just installed a CPA tune and will report back to any changes

so now I'm getting about 36mpg (6.5l/100km) on highway and 30mpg (7.8l/100km) in town with CPA tuning PowerBox Pro,

I paid $174,
here is the link to the 40d options
https://www.cpachiptuning.us/manufac...rive40d-230kw/

even if I only see a 2mpg improvement instead of the 5mpg they advertise, I will break even after 60,000 miles

[Bob777]

I was able to get from my F15 35D 45mpg or 5.2L per 100Km

[BBDDVV]

30D, on average 80% country roads, 20% highway. Some spirited driving now and then...
This is for every fill-up since new. The yearly dips below 8L/100km are highway only, yet with 5 people and a full trunk...
The lowest I saw on shorter trips was 5.6L/100km.