Winter MPG " V " Summer

[pmr]

Hello, The summer mpg was 50.9 and the winter, so far, is 46.1.

Just asking if other UX owners have similar results.

Not sure if this is due to the cold weather, or the new E10 unleaded fuel, or both!

Your comments will be most appreciated.

 

Thanks

Paul

[CypressPhil]

Hi Paul

Sorry to hijack your UX post, but I saw this and thought I get almost identical mpg figures from my IS. I’ve put it down to the cold weather. I guess the engine takes longer to warm up and is required for longer when running the heaters etc. Also Battery performance isn’t as good in the cold. 
 

I have no idea about E10 though, as I’ve only ever used super. Be interesting to hear peoples experiences with E10. I’ve seen plenty of grumbling in the press about it, but always take that with a pinch of salt.

[Moleman]

11 hours ago, pmr said:

Hello, The summer mpg was 50.9 and the winter, so far, is 46.1.

Just asking if other UX owners have similar results.

Not sure if this is due to the cold weather, or the new E10 unleaded fuel, or both!

Your comments will be most appreciated.

 

Thanks

Paul

Not a UX but my CT has dropped from around 65 to around 55 during this recent cold weather. Do not feel it is E10 related because the drop happened more recently.

[Richard1200]

It’s the cold weather. All my Lexus cars have been the same hybrid or not. I am a very low mileage just local driving around and about old fart. Since new last September my second UX reached the high 52’s before now being 48.6 that’s over 1550 miles since new. It will start going up soon. 

[Hamish2015]

I suspect this is more due to lower ambient temperatures affecting engine efficiency and therefore overall fuel consumption. We also use more auxiliary equipment such as heated seats, heaters, lights etc which must consume slightly more energy from the Battery / engine. I don’t think this is in any way a Lexus issue but will equally affect other marques as well.

[David Claridge]

Hello,

My UX F sport was doing 53mpg in the summer and is now at 46.5mpg. I’ve had it for 14 months now. It did the same last winter. I’m sure it’s the ambient air temperature affecting the Battery. My previous petrol only RAV4 was barely affected by the winter, it did 30mpg all year. So I’m still getting 50% more per gallon even in winter with the UX.

Dave C

[ColinBarber]

37 minutes ago, David Claridge said:

I’m sure it’s the ambient air temperature affecting the battery.

Temperature won't affect the usable Battery capacity too much in the UK's climate.

The main reason for lower mpg is heating the cabin - the petrol engine needs to run in order provide you with heat. If you completely switch off your heating system, and just use seat and steering wheel heaters you regain some of that efficiency.

It also takes longer for the petrol engine to reach its minimum temperature on an initial startup before it will allow it to shutdown.

[Roger Bill]

I don't keep detailed records of fuel consumption, but general impressions:

The mpg on all 13 cars I've owned has typically dropped c10% during the winter months irrespective of mileage. During the pandemic my annual mileage has dropped to 3,000 whereas for a number of years I did up to ten times that. 

But my first tank of E10 did also seem to coincide with a drop in consumption - I'm reserving judgement on the effects of E10 vs E5. 

[ColinBarber]

Here's the consumption of my IS300h - definite trend between summer and winter, up to a 15% difference:

 

Much less of a different on my non-hybrid GS, maybe only 8% difference (the spikes are long motorway trips - something you don't see on a hybrid as the economy is more consistent).

 

[EvilRacer329]

I've kept a record of every fuel up for every vehicle I've owned for over ten years, and without fail all of them get better fuel economy in warm weather than cold. Motorcycle or car, it's all the same, with 10-20% difference completely normal. Engines run rich while cold in order to compensate for fuel vapour condensing on the inside of cold engine parts rather than getting sucked into the cylinders and burned cleanly. The longer they have to run cold, the more extra fuel is wasted.

As other commenters have mentioned, the hybrid system will also fire up the engine in order to meet the demands of the climate control system. On a cold day, after stopping the car, you can literally watch the engine temperature gauge plummet as the heater matrix gives up its heat to the cold air being drawn in by the cooling system. To help, you could set your climate control to recirculate or even switch it off entirely and rely on heated seats/steering wheel if you have them.

But the worst is if you fire up the engine and let it warm up for minutes on end while you scrap the ice off the windshield. Yes, the hybrid system means that some of that energy will be recaptured in the Battery, but modern engines don't need to warm up before you start driving, assuming you're not going to bury the throttle and thrash it right form the get-go. Get in the car, switch it on, and hit the road.

Nick

[edith]

get about 55mpg both winter and summer