I have lexus IS 350 AWD 2014 since winter started here in DUBAI I'm getting poorer gas mileage from 29.1MPG to 27MPG mostly highway driving 51miles to and back form work..
ANY IDEAS

 

^^ I am not sure what a "winter" is in Dubai compared to winters in Canada but I can assure you that losing 1.9 mpg in winter or colder conditions is certainly not out of the normal and quite common. I would not worry about it at all....

 

^^ Agreed.
It would be nice to know what Winter temps are like in Dubai.
Here in Canada Summer where I am can be as hot as 35C, and Winter as cold as -35C (these are rough averages).
So Winter time you certainly waste more fuel as the vehicle takes longer to warm up and get to its more fuel efficient operating temperature.
Also the fuel stations change the blend of gasoline slightly for the Winter months, so that also has a small impact on it.
Usually Spring and Fall are the best times for fuel economy as you don't need the A/C in Spring and the car doesn't take too long to warm up in Fall.
Summer you're blasting the AC, so that uses a little more fuel, and Winter it's cold, so that uses more fuel to warm up and keep the vehicle warm.

 

If it makes you feel better I have a 350 as well and I get about 16 mpg city, BUT I"m driving like 1.9 miles to work. I've even gotten as low as 12 mpg with such a short commute which is absolutely horrendous. your highway mileage is decent for winter and all highway, I wouldn't worry too much, check your tire pressure as well.

 

2014 IS350 FSPORT AWD

Winter hit and mpg dropped from 19.2-19.5mpg city/highway to 16.5-17mpg city/highway. Temps hover in the low 20’s to zero degrees. Terrain in western PA is very hilly also. Zero mods.

Is this normal?

What are others experiencing in the northeast? Also put a bottle of Techron in it just before winter hit.

 

^^ Of course it is!! Every car, not just the IS, will experience a drop in fuel mileage in the winter.....

Here is a thread on this very topic (was on page 2) - I just did a quick search and bam...there it was

https://www.clublexus.com/forums/is-...in-winter.html

 

Winter blend fuel additives DO cause lower MPG’s

I have lower MPG for other reasons..!!




Joe Z

 

Engine need warm up, when the weather is coldest your engine need more time to warm up and to be efficient

 

Yeah and for what it's worth, @ShrinkDoc , your MPG drop is only a little more than what I saw in winter in my 2016 IS 300 AWD. I typically got about 19 MPG in the summer and around 17 in the winter.

With my 350 RWD, it seems like the drop has been less noticeable, maybe only 1 MPG, but I've also been doing a decent amount of longer trips so that probably helps - and also, in ATL the winters are not as cold as they were back in Kansas City when I had the 2016.

 

Yes It's the same for me, in winter when I drove a long trips the MPG is better than a lot short trips.

 

Hey Guys thanks to all of ya for your feedback...
guess what my fuel mileage kept getting worse, hooked u a scan tool and found my car to be running too rich. The mpg fell form 28 to 25 in the highway...
It turned out to be a dirty MAF sensor !!! Of all the things i thought could have gone bad it was just a dirty MAF sensor plus there was a loose wires in my MAF sensor which triggered a Check Engine light later on...
After reconnecting the wire and cleaning the MAF sensor..mpg is back to 29 to 30 on highway.....
Thank to all of ya once again...

 

Are you running an oiled engine air filter..??


Or just the normal build up of sand / dirt in your regional driving conditions.


Joe Z

 

Ya I run KNN filter, after I found my MAF was dirty I finally cleaned my filter after 16months….. guess that’s on me….
I often do you need to clean your knn filter?

 

Oiled Filters can create problems for the MAF sensor element over time..

In your region I would probably clean the MAF sensor every oil change.

Joe Z