MiPHEV's Highway Trip Economy, Trailering, and Fuel Logbook Data

[MiPHEV]

I recently bought a used 2019 with ~68,000 miles (110,000km) on the clock for use this summer as a sort of test mule to determine if the newer 2023+ Outlander PHEV might be right for our next longer term car. I am using this as a backup commuter and a highway trip car, and will be testing long highway trailer towing and car camping this year as well. This is a US spec version with the 2.0L engine and the small 12kWh capacity battery pack. I ordered it sight unseen from an online car buying outfit and put it into service once we picked it up in January 2024.

I have a reasonably good, regular long range trip I'll be making this spring and summer that is about 1,000 miles (1,600km) round trip. I'll start with a full charge at each end, and I've worked out which drive modes suit me best for economy on the initial three trips I can report in this first post. I've been recording weather conditions like temperature and wind as well as which drive modes I've used on a given segment for comparison purposes. Starting from the 2nd trip onward, I have used the PHEV Watchdog app to provide some additional information from the car's OBD interface. My Fuelly logbook contains all my tracked data and is located here: https://www.fuelly.com/car/mitsubishi/outlander_phev/2019/avm1/1259051

Trip 1: January 2024
Conditions: 10 to 19F (-12 to -7C), 60-75 mph (96-120 kph), high winds and some snow/ice
Drive Mode: Save Mode on all highway segments
Worst tank: 23.2 MPGus (10.14 l/100km, 27.8 MPGuk)
Best tank: 27.38 MPGus (8.59 l/100km, 32.88 MPGuk)
Overall: 25.79 MPGus (9.12 l/100km, 30.97 MPGuk), 956.5 mi., 37.083gal., $0.116/mile, $110.80 total

Notes: The car stayed in series mode the entire trip, the parallel mode engine coupler only kicked in on a few times during heavy acceleration or hill climbs. Initially suspected that this was due to a cold drive battery, but did not have PHEV Watchdog to get that information from the car. The bad economy is probably down to using series hybrid mode and cold temperatures.

Trip 2: March 2024
Conditions: 22-61F (-5 to 16C) low winds, dry
Drive Mode: "Volting" (Charge mode to 89%, discharge to 50%, repeat) departure trip, Normal mode return trip
Worst Tank: 26.87 MPGus (8.75 L/100km, 32.27 MPGuk)
Best Tank: 35.32 MPGus (6.66 L/100km, 42.42 MPGuk)
Overall 31.15 MPGus(7.55 L/100km, 37.41 MPGuk), 905.6mi, 29.069gal., $0.108/mile, $97.41 total

Notes: Generally good conditions, tested Volting mode, and Normal mode on the return trip. Normal drive mode seemed to return the best results for highway travel. First trip playing with PHEV Watchdog app, battery state of health (remaining capacity) 71.5%, 28.6Ah. Cruise 67 mph/108 kph.

Battery Condition:

Trip 3: April 2024
Conditions: 46-69F (7.8 to 20.5C), 10-12mph headwinds departure trip, similar crosswinds last 2 hrs. return trip
Drive Mode: Save+Eco (aborted, see notes), Normal+Eco on highway, Charge+Eco mode prior to in-town/construction
Worst Tank: 29.9 MPGus (7.87 L/100km, 35.91 MPGuk)
Best Tank: 35.37 MPGus (6.65 L/100km, 42.48 MPGuk)
Overall: 32.61 MPGus (7.21 L/100km, 39.16 MPGuk), 1239.9mi, 38.021gal., $0.105/mile, $129.95 total

Notes: Initial plan was to try for a trip on Save mode in warmer weather. Save mode attempted right after merging onto the highway but would not lock into parallel mode operation, switched back to Normal mode to wait for battery to fully heat up from its 44F (6.6C) starting temperature. It took ~3 hours to heat up to ~77F/25C normal operating temperatures. Tried again, Save mode will not lock up into parallel operation, stays in Series mode at all times even at full temperature, tried 3 times, further testing of this mode aborted due to poor economy prospects.

Departure trip was into moderate headwinds. You can clearly see the impacts in real time, if you watch the Eco Information pane of the PHEV Vehicle Information screen on the MMCS. The EV Drive Ratio in good conditions will hover around 40%, and the Avg. Mile/kWh remains around 3.0 on the highway. In adverse conditions like the headwinds on the departure leg, the EV Drive Ratio drops over time to around 32% and the Avg. Mile/kWh fell to around 2.5. It is also easy to see how much load is occurring from the wind by watching the Charge/Eco/Power dial gauge - in good conditions it will cruise low in the green Eco range on level ground, and as the conditions deteriorate the needle will climb and remain at a higher average position. The Avg. Consumption on this screen for the engine in the headwind displayed 29.9 MPG and in good conditions on the return trip settled around 36 MPG, until I hit the crosswinds near the end of the trip where it dropped to around 34.x MPG. Cruise 67 mph/108kph.

Departure PHEV Watchdog Trip Report:

Return PHEV Watchdog Trip Report:

Battery Condition changed for this trip, 0.1AH capacity lost, down to 71.3% state of health:


Final thoughts on this trip: I've been using Charge mode in anticipation of all in-town, low speed segments, construction or collision delays indicated ahead on Google Maps, exiting for fuel pit stops, etc. I usually have been giving it about a 20 or 30 minute Charge cycle before slow speeds are expected, depending on how long I anticipate the low speed segment will last - trying to make it through the low speed areas without needing to resort to the lower efficiency series hybrid drive mode.

I also engage Charge mode on any highway on ramps, and also on longer hill climbs, to keep it from staying or switching into the EV mode cycle - I do this to lower the battery current (C rate) demanded from the cells at those high power impulse moments to let the generator take some of the intense high amperage load off the aging battery cells.

More trips to follow...

 

[kpetrov]

There is no need for so many complicated fuel comparison experiments in all kind of different driving conditions... incomparable by nature.
Parallel mode is better than Series mode, that's a fact. Parallel mode is there for a reason otherwise nobody would have complicated the vehicle... it could have been just a simple Series mode.
All one have to do for best efficiency is to use the engine only in Parallel mode. Charge mode doesn't use more fuel when used properly on highway so use it to avoid using the engine in Series later. Don't accumulate more charge then what one needs to finish the trip as well.
I suspect it's better to use it and cycle in low battery state of charge from 10% to 60% but don't have any actual info on that.

 

[MiPHEV]

Yup, if only there was a simple selection for parallel only mode! Also, it shouldn't have taken so long to determine that Save mode is actually utterly useless on this car, perhaps it only locks out parallel mode on a degraded battery, but at any rate it has no use case I can think of other than to waste fuel.

I don't think there's anything really complicated or difficult about fuel and maintenance log books, in fact it's the only way any value can be added to any discussion about economy, many people self-edit or only remember the best case (or worst case) results, or even worse, report fuel economy from dashboard readings, also useless. I've never owned a car where I didn't keep a fuel and maintenance log, so it seems alien to me to not track expenses on what is usually the second-largest cost center of modern life for most people!

For my purposes, this is necessary as I'll be compiling data to compare to the running costs of other competing vehicles as well as for upcoming modifications to this vehicle, and for that, you need real, hard data, and most anecdotal reports from social media are really not very useful at all due to poor methodology. Sample size is also quite critical in finding a real mean from inherently noisy source data - it makes it infinitely easier to come to a statistically significant conclusion. So, I selfishly want many samples of reasonable quality data, and even though this car has been on sale for many years, there is not an abundance of high quality data to be found; the best so far is on fuelly.com - but I also wanted more weather and other trip data for my purposes that is often not included in those logs.

At any rate, every serious forum I've ever participated on that was concerned with fuel economy or efficiency only focused on real fuel log book reporting and all other anecdotes or "drive by reports" were discarded as noise, because really, that's all they are. This was true for the diesel car focused VW TDI Club, Ecomodders, and even the heavy duty truck towing forums. In that case, business fleet managers were some of my best resources, as they actually are very, very good at focusing on data-driven metrics. I'll report my data here for others as well, as fuel economy and efficiency is a question that seems to come up a lot for these types of cars! So, this data is already being collected for myself for a higher signal/noise ratio for my experiments, and if even one other person finds it useful, that's just a cool bonus, imo.

Just as one example, I was comparison shopping the Outlander against the RAV4 Prime, and if you look at our EPA numbers, the RAV4 is rated at 38 MPG and the Outlander at a meager 26 MPG. I had to dig, and dig, and dig, to find out that in fact, for most purposes, and especially highway purposes, there is actually very little difference in economy between the two cars, so I had to make a best guess on deciding to try the Mitsubishi... Even then, the data I was able to find was pretty poor quality and of course mostly based outside the US - so I had to convert units regularly as well which is just another hurdle that is more efficient to take care of on the reporting, rather than the researching side, for less duplicated effort by multiple readership.

 

[MiPHEV]

I suspect it's better to use it and cycle in low battery state of charge from 10% to 60% but don't have any actual info on that.

I actually bookmarked this post from Trex where he noted that the fuel economy does seem to drop above 5 bars on the Energy Flow display, so I think this is a good thought to keep in mind; probably why Normal mode is ending up as the best case, or near best case highway mode on the drives I've done so far as well!

 

[kpetrov]

Yup, if only there was a simple selection for parallel only mode!

I don't think there's anything really complicated or difficult about fuel and maintenance log books

For my purposes, this is necessary as I'll be compiling data to compare to the running costs of other competing vehicles as well as for upcoming modifications to this vehicle, and for that, you need real, hard data, and most anecdotal reports from social media are really not very useful at all due to poor methodology.

Doesn't your PHEV keeps Parallel once Charge is selected?
Beside engine warming period mine will stay continuously without dropping Parallel while in Charge mode.

I agree on the data but I am not even looking for it anymore... except to compare with other vehicles like you have said.
Since I can keep it in Parallel while in Charge there is no any scientific scenario where I can get better efficiency than that.

 

[MiPHEV]

Doesn't your PHEV keeps Parallel once Charge is selected?
Beside engine warming period mine will stay continuously without dropping Parallel while in Charge mode.

I agree on the data but I am not even looking for it anymore... except to compare with other vehicles like you have said.
Since I can keep it in Parallel while in Charge there is no any scientific scenario where I can get better efficiency than that.

It does, as long as the other conditions are met, warm enough battery, high enough speed, etc. But, it also stays in parallel in Normal mode too, as long as those same conditions are met, so either mode works the same for highway use, except Normal is the "easier" default I suppose. What I'm getting at is more of a smarter car where it had a mode or button where serial mode was never needed or engaged at all - like a predictive algorithm that would keep it automatically adjusted for max economy, never running the engine below 40 mph, keep the battery warm enough, etc - just dreaming as far as that goes... I do like the fact that Mitsubishi defers all the ability to the driver to manage things though in lieu of such non-existent predictive drive modes!

 

[kpetrov]

It does, as long as the other conditions are met, warm enough battery, high enough speed, etc. But, it also stays in parallel in Normal mode too, as long as those same conditions are met, so either mode works the same for highway use, except Normal is the "easier" default I suppose.

I suppose your vehicle is new... give it few years and it won't stay in Parallel while in Normal.

I don't like Normal at all.
It will leave me without any battery backup for unforeseen traffic etc.

 

[AndyInOz]

It does, as long as the other conditions are met, warm enough battery, high enough speed, etc. But, it also stays in parallel in Normal mode too, as long as those same conditions are met, so either mode works the same for highway use, except Normal is the "easier" default I suppose. What I'm getting at is more of a smarter car where it had a mode or button where serial mode was never needed or engaged at all - like a predictive algorithm that would keep it automatically adjusted for max economy, never running the engine below 40 mph, keep the battery warm enough, etc - just dreaming as far as that goes... I do like the fact that Mitsubishi defers all the ability to the driver to manage things though in lieu of such non-existent predictive drive modes!

For the car to be in parallel mode all the time, you'd need an extra gearbox on the engine.

 

[Stevepl11]

What I want is a simple way of preventing the engine starting when EV range drops to zero and I have 2km to go to get home where i can Plug In.

I will, and do, use save and or charge mode to acheive several goals. 1/ get the engine up to full operating temperature for as long as possible, 2/ avoid running the engine for short periods like just before arriving home, 3/ use all the EV range if the trip exceeds that and run out (--- displayed) as I get home.
If the engine starts within the last couple of km, it means I misjudged the distance. But if the car had run out of fuel for example it would still run on battery power with some limitations, so how can I trick it into being "out of fuel"?

 

[greendwarf]

Get rid of the car and buy a BEV - simples!

 

[kpetrov]

What I want is a simple way of preventing the engine starting when EV range drops to zero and I have 2km to go to get home where i can Plug In.

I will, and do, use save and or charge mode to acheive several goals. 1/ get the engine up to full operating temperature for as long as possible, 2/ avoid running the engine for short periods like just before arriving home, 3/ use all the EV range if the trip exceeds that and run out (--- displayed) as I get home.
If the engine starts within the last couple of km, it means I misjudged the distance. But if the car had run out of fuel for example it would still run on battery power with some limitations, so how can I trick it into being "out of fuel"?

Just install the engine kill switch and you will be reborn.
I bought the vehicle specially for its full ev capability architecture and lack of complicated transition.

 

[MiPHEV]

Trip 4: April 2024
Conditions: 37-55F (2.8 to 12.8C), 15mph crosswinds departure trip, 10mph headwind last 4 hrs. return trip
Drive Mode: Normal, 67-68mph cruise speeds
Worst Tank: 29.3 MPGus (8.03 L/100km, 35.19 MPGuk)
Best Tank: 39.45 MPGus (5.96 L/100km, 47.38 MPGuk) (~15% electric charged/city driving)
Overall: 32.14 MPGus (7.31 L/100km, 38.6 MPGuk), 1111.5mi, 34.585gal., $0.114/mile, $126.38 total

I had hoped for better/warmer and calmer wind conditions this trip, but the weather did not cooperate. Slightly lower overall economy. A new discovery for when parallel mode is disabled/locked out - when you hit the second Refuel Warning, when the fuel indicator starts blinking rapidly, this disables access to modes like Charge and Save, but it also completely disables the parallel operation in Normal mode, too - further decreasing the highway range available in the last gallon of the tank, which was a slightly unpleasant surprise! Fuel prices went up slightly as well, for a total trip cost increase of 8.6% per mile.