4x4 Action Group

Hi,

Can the ambient temperature have an effect on the fuel consumption of a diesel motor?

The reason I ask is because my datsun's fuel consumption has increased by approximately 1,5 to 2km/l since October this year.

I cannot think of any other reason why it would have increased:
1) Tyre pressures are closely monitored every week;
2) No mods were fitted;
3) Driving style has remained the same.

The motor has only done about 26k. It is close to its service and I have noticed the engine oil is darker than usual

What say the experts?

FIY - where I live, temperatures can increase from an average of 21 degrees (winter) to 38 degrees in summer.

Cheers
The cheap coffee guy

Mmmmm.... You usually only dice the 2.2 rangers but unwittingly the same guys you are racing have bought 3.2 rangers in a conspiracy to oust you as the Oshakati stop-to-stop-bakkie-drift-king. Now you still dicing the same guys but, unbeknownst, used more sauce to win the pink slips.

That or this is a part of a smokescreen to convince swambo you did not go on that golf trip you said you were not going to go to....

There. I solved it.

Gee I need to go and search deep into my old diesel studies. So please what I post here might not be 100% correct.

First the higher ambient temp the less effective the inter-cooler becomes. The hotter the charge the less engine efficiency.
From what I can remember that with diesel fuel temp higher than 40deg you lost up to 6 % in engine efficiency. The reason why most modern diesel vehicles are equipped with diesel coolers. But ja when temps soar past 40deg in Namibia and the Northern Cape as per summer norm I guess inter and diesel coolers becomes sort of usless.

So yes in hot conditions a diesel engine becomes less efficient

grips wrote: ↑

Tue Jan 08, 2019 4:15 pm

Gee I need to go and search deep into my old diesel studies. So please what I post here might not be 100% correct.

First the higher ambient temp the less effective the inter-cooler becomes. The hotter the charge the less engine efficiency.
From what I can remember that with diesel fuel temp higher than 40deg you lost up to 6 % in engine efficiency. The reason why most modern diesel vehicles are equipped with diesel coolers. But ja when temps soar past 40deg in Namibia and the Northern Cape as per summer norm I guess inter and diesel coolers becomes sort of usless.

So yes in hot conditions a diesel engine becomes less efficient

Very interesting !! Never to old to learn !!
So those Arabs in the desert use a lot of diesel ??? How does Petrol do in heat , Grips ??

Aircon... And airfilter

Sent from my S60 using Tapatalk

Thanks Grips!

Mad Manny wrote: ↑

Tue Jan 08, 2019 6:46 pm

I have the answer Damassel:- Aircon Use...

Mooi man.

Can't fault you for being pragmatic.

I bought the datsun last year October. With aircon on 90% of the time - had better fuel consumption then. It is a bit hotter this year - the reason why I asked.

Hedgehog wrote: ↑

Tue Jan 08, 2019 7:39 pm

Aircon... And airfilter

Sent from my S60 using Tapatalk

Interessant dat jy die lugfilter sal noem. Ek het dit ook vermoed en derhalwe blaas ek dit een keer 'n maand met die kompressor skoon.

Dalk moet ek 'n filter koop en kyk of dit 'n verskil maak. Thanks Andrew.

NEW wrote: ↑

Tue Jan 08, 2019 3:27 pm

Mmmmm.... You usually only dice the 2.2 rangers but unwittingly the same guys you are racing have bought 3.2 rangers in a conspiracy to oust you as the Oshakati stop-to-stop-bakkie-drift-king. Now you still dicing the same guys but, unbeknownst, used more sauce to win the pink slips.

That or this is a part of a smokescreen to convince swambo you did not go on that golf trip you said you were not going to go to....

There. I solved it.

Mens dice nie daai fords nie - die goed het soveel torque dit kan 'n brakpanner van sy sussie af trek.

Ricoffy wrote: ↑

Wed Jan 09, 2019 7:17 am

Hedgehog wrote: ↑

Tue Jan 08, 2019 7:39 pm

Aircon... And airfilter

Sent from my S60 using Tapatalk

Interessant dat jy die lugfilter sal noem. Ek het dit ook vermoed en derhalwe blaas ek dit een keer 'n maand met die kompressor skoon.

Dalk moet ek 'n filter koop en kyk of dit 'n verskil maak. Thanks Andrew.

Wanneer is sy volgende diens? - As jy n auto het - check dat die box lockup in die ratte
Het jy nog dieselfde bande op? - wanneer laas het jy bandruk gecheck?
Word jou wheel hubs of rims warm as jy ry? (Voel hulle nadat jy gestop het) - kan bearings wees of n briek wat bind

Anders... ry jy dalk net harder noudat jy gewoond is aan hom

Doen `n brondstof toets in die nag en pos die reultate hier.

Spoke to a friend tonight he also have the new Navara. His consumption dropped to 7.3km/l while on holiday.

You most properly have blocked Cats.

You will know there is some little knoppie you need to push, Find a nice private road. Bliksem that Navara as hard as you can while pressing that knoppie.

grips wrote: ↑

Wed Jan 09, 2019 10:48 pm

Spoke to a friend tonight he also have the new Navara. His consumption dropped to 7.3km/l while on holiday.

You most properly have blocked Cats.

You will know there is some little knoppie you need to push, Find a nice private road. Bliksem that Navara as hard as you can while pressing that knoppie.

Hi Grips,

Eerstens baie dankie vir die advies. Ek het net 'n dpf knoppie en volgens my verstaan is die dpf en cat afsonderlike items, maar tog verbind aan mekaar.

Ek het die manual gaan lees, en volgens Nissan gebeur die regeneration process automaties as ek vir 'n seker afstand vinniger as 80km/h ry op die oop pad. Ek kan die knoppie druk om die proses manually te doen, maar die boekie seg niks oor dit druk en ry nie. Die boekie praat net oor die bakkie stilhou, die knoppie druk en wag todat die proses klaar is.

Ek moet ook noem dat die dpf waarskuwingsliggie nog nie aangekom het nie.

Dink jy dis veilig om die knoppie te druk en die kar te bliksem op die oop pad? Of moet ek maar net sewe soorte kak uit hom ry vir so 60km sonder om die knoppie te druk?

Barometric pressure also has an effect along with the air temp. Low barometrics are associated with rain etc while high are associated with good weather. Your vehicle will probably be fitted with barometric sensors. A low pressure weather system could affect consumption negatively