Fuel economy

[MywifesZ4]

Just lately SHMBO has complained of low fuel economy on her Z4 2.5 auto , usually she was returning around 26 mpg , but just lately that has reduced to 19 mpg . She does the same journey everyday around 10 mile to work and back, car is still running smoothly not jerky or miss firing , all tyres are inflated to correct psi , I understand that shorter journeys will result in lower returns but such a dramatic drop is baffling.
She tend to use Morrisons fuel unleaded as apposed to super , but always had so unless they have change quality of fuel can't see that being he cause .
Any Thought

 

[mr wilks]

You will always see a reduction in MPG no matter what fuel or car in the colder months :wink:
the car is using more fuel to operate until engine warm's up .
ps / has she released the handbrake ?

 

[andysat]

+1 on the colder months quote.

 

[Z4Bob]

Seems a bit low mpg. We get at least 30 mpg from our 2.5 auto and that includes sitting in traffic on way to work.

 

[MywifesZ4]

I thought it may be outside temperature , her journey is very short tbh and would think its does not have time to warm up before she gets there or back .
I will have to give it a run on same journey over weekend to see if she has developed "heavy foot" during the cold snap

 

[Maniac]

Snap... mines gone down from 26 to 22 already...

 

[andysat]

Snap... mines gone down from 26 to 22 already...

 

[Swiftly]

I have noticed a drop of about 4 mpg with the arrival of the colder weather

 

[mmm-five]

Only seen a 1mpg difference on the ///M

 

[slick]

mines dropped 6MPG in the cold :?

 

[bigshurv]

Lights on, heated rear window on, demister on full for 10 mins every journey,wipers flailing madly away,car struggling to warm up and get to it's efficient operating temp. Years ago you'd see many vehicles with half the radiator blanked off during winter,this was so they'd run more efficiently.

 

[malibudave]

Plus in winter the garages switch to winter fuel!!

 

[GregZ4]

Mine has gone down 0.3.
However I used to have a 325i Sport Auto that dropped off the edge of a cliff in winter.
Must be auto vs manual?


Sent from my BlackBerry 9300 using Tapatalk

 

[Maniac]

Lights on, heated rear window on, demister on full for 10 mins every journey,wipers flailing madly away,car struggling to warm up and get to it's efficient operating temp. Years ago you'd see many vehicles with half the radiator blanked off during winter,this was so they'd run more efficiently.

Not to mention Air Con on too to keep the moisture off the windows... at least, I do.