Really bad MPG since winter hit??
 

Hey guys, so since I got the X5 it has been super good to me and my wife other then the 2 back tires going flat at the same time :rolleyes:.

But since the cold weather has hit here in Calgary Alberta the x5 has dropped in MPG like a lot!! in the summer it got just around 800 kms now since winter has hit, its not even getting 450 kms to a tank... there is no check engine light or any warnings.

In the summer I put in a cold air intake, its still on the x5, should I put the stock intake back in to it?

Could it be that the intake is sucking way too much cold air and causing the engine to run richer then it should that makes it drink gas like its nothing?

thanks for any help

Tire pressure, 'winter gas' in CDA?
Not a fan of 'cold air' intakes...
GL, mD

Mine has lost some MPG too. When it was nice out I was getting around 450+ miles to a tank, now it's down to around 400.

Do you let your car run to warm up? Warm up time can decrease your MPG as the car is using gas, but not gaining mileage.

Also, cold air intakes are kind of a waste. A good, drop in filter like a K&N, Dinan, Pipercross etc... will do the job.

Most "cold air intakes" aren't even cold air. It's a pipe and a filter that sits right in the engine bay, in fact sucking in HOT air.

what'a a good city mpg value?

In a 4.4? I get around 16 if I drive nicely... If I drive like I normally do around 14.5-15mpg.

Since winter hit I'm getting around 13.5-14mpg.

Omg my 3.0 would struggle to get 300 for a tank. now I'm barely reaching 250 before the gas light comes on

"city" driving is different for everyone. For example, where I live the speed limit is 30 and you can barely go 300ft without hitting a stop sigh or a speed bump and where my cousin lives in Florida it's like 1.5miles between red lights

The cold air intake will not cause a rich condition. The O2 sensors measure the exhaust gas and cause the ECM to adjust the fuel injector pulse width to deliver the correct air/fuel ratio (cold air will cause a wider pulse and deliver more fuel, and make more power).

Even with a carb'ed motor, cold air causes a LEAN condition if jetting was set for hot weather.

Same here. Our OC streets are somewhat wide and we can hit 50mph to 60mph without much stops if all the lights are synch'ed. Traffic is also somewhat light at my time of commute. Even that, I cannot reach 350 for a tank.

I guessed we have a heavy foot?

I can barely get to 40 without getting to a stop sign I'm not even talking about a red light

Any fuel injected vehicle tend to run richer in the winter. Install of bottle of this to make sure your injectors are clean. My gas mileage jumped after a bottle of this and a full tank run through.
LIQUI MOLY - Motor Oils, Additives, Car Care - Products - Fuel Injection Cleaner

Well the "cold air intake" I got it because I love the sound of the V8 with it on, also the X5 was averaging 800+ kms in the city in summer time.

it only has 95k on it not miles I do not wait tell the X5 to warm up to drive it, as it states in the manual start it and drive right away but slowly, I tested this last time it was -30 or so I let it sit there to warm up and after 15 mins the needle wasn't past the blue temp marker so I know the X5 warms up better when u start driving it right away.

Also since I got the X5 I tested like 7 gas stations and the best gas mileage I got was from PETRO CANADA was the best kms I got to the tank and 2s in line was SHELL V POWER gas.

I only put 91 oct gas in it, I have tried 94 from PETRO CANADA but the x5 didn't show any increase in power or mileage.

I also try all of the time to fill from PETRO CANADA gas stations only and not get mixed gas from other stations.

On last nights fill up I added a can of SEA FOAM to the tank, but im going to put the stock intake back in just for the winter and see if I get somewhat better gas mileage in the winter

Well im up in edmonton and got 436kms on a tank last week. Thats in my 4.6, my 4.4. got around 470kms the same interval. Its harsh and sitting in traffic isnt helping.

but to lose 300kms+ wow lol

the octane rating has nothing to do with energy packed in a liter/galon of fuel... all it is a retardant index that prevents the fuel from self-igniting under high pressure (sport engine, higher compression ratio, fuel self ignites before spark, piston knocks!!)... since that type of fuel is marketed to "sports" cars, that tend to be more expensive, the refineries sell it for more money (even though it is less "flammable") and also can afford adding more detergents and other additives, to make it more attractive to potential buyers...

Why the mileage has gone down in winter - i have no idea... mine has gone down a bit too, to about 16 MPG in a 2006 4.8iS, my driving is mostly highway but sometimes the highway is moving slower than city traffic... lol... I pull about 400 miles off a tank, give or take...

Moe, I am not sure how you were getting 800km+ in the city... i never get more than 750-800km on a highway when driving at around 90-100km/h... but to get 800 in the city... i've never heard of anyone getting anything even close to that... in a diesel maybe but not with a 4.4... i average about 500 km in the city (i do have a heavy foot) but in order to get 800 you would need to get around 10l-11l/100km at most... i think our cars are rated at 15-16l/100km in the city and 12 on the highway...
And i do get a bit of decrease in fuel consumption, but nothing significant

Biggest impact on fuel mileage is the driver and driving habits.

2nd is probably ethanol content of the specific fuel (the actual content, not what they claim it could be on the dispensing pump)

Winter mileage drops are often associated with more idling time. Also, check tire pressures since they will drop with the cold ambient temperature.

i put air in the back 2 tires tonight, my wife drives the x5 mostly and i tell you she has a light foot lol


ukrcan, lol in the summer days i was getting 650 to 750 with 1/4 left in the tank my dash reading thingy was reading 11.2L per 100 kms and with 1/4 tank left the dash was reading 160+ kms to E lol now its around 13.5L to 100kms :S

whats shocking to me is that my 2002 jeep tj inline 6 gets the same damn mileage year round 300 to 350 if i push it to 350 lol along with my 328i in the city i get 450 to 550 and over 800 kms highway, but seeing the x5 average 450 and the light comes on just makes me cringe from what it got in the summer damn

I do know that ethanol is added to almost all the damn gas nowadays, but some shell gas station if you look around it says right on the pump that shell V power 91 oct has no ethanol added

I wish Shell had 0 ethanol here in Washington. Every grade has at least 10% at all the top tier stations. You have to go no name indy stations for the ethanol free. I'll stick with Chevron and Shell.
Wow, and I thought my wife getting 16mpg in our 4.6 was bad. I can tell her to keep up the good work now :) We've gotten 21-22 on the highway getting around 500 miles per tank (we try to fill up before it goes below 1/4).

At your own discretion, you could remove the cooling fan on the 4.4 and early 3.0 (late 3.0 has an electric fan) during winter. This helps the engine warm up faster and get better gas mileage. Make sure to store the fan vertical though. I leave ours off until end of May and I think I probably could just leave it off through the summer if we just stayed on the peninsula out here where it doesn't really go above 70 degrees and no traffic.

Odd, my 3.0 gets somewhere close to 800km per tank. It might be that I coast as much as I can and accelerate gradually. I haven't event started doing my mad scientist mods yet. :thumbup:

I once got 35 mpg in a 1/2 ton pickup, but I also caused a bad misfire, and some of my experiments have been... catastrophic. :D

I'll go middle ground on the X and let you guys know if I get any good results.

Do you guys get the oxygenated gas up north? We get it with MTBE in it and that zaps mileage.

moezer, I have noticed a huge decrease too but mainly because i've been running my x5 to heat up till i drive it away since its been parked outside so far this winter as the new garage is not uilt yet. I also moved from Airdrie to inner calgary and my kms/tank have gone from 650kms/tank to 450 kms/tank now :(
its crappy the winter we've had so far.

ukrcan, i get the exact same kms/tank as you.

city in the winter I get 15.5/100km, city in summer about 14/100km, highway in summer about 10.4/100km

As a 3.0d owner shouldn't really be posting here, but I used redex additive yesterday when i filled up and my consumption went up from 29.2mile per gallon to 33.1 mpg....I guess the additive must have done something as nothing else has changed on the vehicle, and the gas station and fuel i use is the one i always use.....

I was surprised by the x5 when I got it and I saw it was getting almost 800+ at 1/4 before the light lit up, in fact I was happy as hell when people asked me "oh wow 4.4 v8 must be a gas drinker" I loved the look on there face when I told them I was getting around 800km to a tank lol

Im going to see after I put the sea foam in it what I get on this tank.

the thing is on my 2002 jeep tj I have always gotten around 300kms a tank winter or summer so when I saw the difference in the x5i noticed a crack in my visa :bustingup

wow 11.2L per 100kms... you gotta tell me how you do it... do you do a lot of highway driving?

deer foot? when my wifes goes to work? but deerfoot is always packed in the morning and afternoon so I don't think that makes a diff lol

I've only ever gotten 800-880kms out of a tank when cruising at 100-110 kms/hr MAX from here to Montana. I've never gotten anything near that in the city or even airdrie to calgary highway driving.
I think the X5 4.4 and 3.0 is an OK vehicle on fuel consumption but I have noticed in the last 2 years my consumption dropping a bit too. I use seafoam every 4-10 tank fulls to clean it out.
use it in your oil for 150 kms before an oil change too. does wonders

well u have seen the x5 your self and how clean it was/is im still a few k km from an oil change but will add it when it comes time to

Winter Weather Cuts MPGs by One Third: Study » AutoGuide.com News


i just did another fill up and filled up my spreadsheet for last few fill ups i had - i noticed that the fuel economy has broken the 16 MPG threshold and is now 15.3 MPGs...

I think I am due for another hot oil change and a Liqui-Moly flush... can use some injector cleanings too - i've heard good things about Jetron by Liqu-Moly...

any other suggestions?

hello, a few months back I was doing predominantly motorway driving after adding redex my mpg went up about 3mpg , not sure they sell it in the u.s, now that I have started town driving - schools runs etc it has dropped by 3mpg....maybe i'll add another dose of the stuff see what happens

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_16 0212_langId_-1_categoryId_255221

It is sold under various names here. Paint thinner, solvent, white gas, camping fuel, parts cleaner, lighter fluid. All are similar. The one you link is described as being most suitable for cleaning carburetors. I last had a vehicle with a carburetor in the early 1980s.

It is generally a much better approach to use good quality fuels that include proper detergents, instead of dodgy fuels that leave deposits, and require these sorts of solvents to shift.

Marvel Mystery Oil is a great fuel additive also add it to the oil 1000 miles before oil change to flush waste. Used it since the 70s.

Well i fill up at a local esso gas station, no idea how good the fuel is there, sorry for the wrong link, the one i used was the one for complete fuel system clean, injectors etc....

So, where do I get Top Tier gasoline in the northwest that does NOT have ethanol in it? Considering our X's were never designed to run on oxygenated fuel year round, I disagree with a 'software' fix correcting a physical incompatibility.

According to pure-gas.org, many stations in Washington (The State), check it out:

Ethanol-free gas stations in the U.S. and Canada

Thanks, I've known about that website, haven't checked it out for at least a year...looks like I still have to drive at least 3 hours to find a Chevron with 92. Neither Conoco or 76 (2 hours away) has anything better than 90. Won't work in the 4.6. I could always get a Pacific Pride account and fill up locally and add in a bottle of the 'pure' Techron per tank...
I'll make a determination on what to do when I do my VPG or chain guides this summer. If the injectors look horrid, it may be time to make the change.

@omodos, Esso is on the list of Top Tier retailers.

Osmodos isn't in the US, so won't have access to the Top Tier program.

I don't put too much stock in it, and wouldn't cross the road to get to a Top Tier station myself. It is only focused on one specific issue (valve deposits) and doesn't at all address any other quality issues. I think using a name brand fuel from a station with reasonably high daily volumes is far more important than the Top Tier label.

And since the Top Tier requirements includes a minimum 8% ethanol content, I prefer to use a non Top Tier gasoline without ethanol. Our federal ethanol requirement where I live applies to all fuel suppliers, but it is a percent averaged across all their sales, not a percent on each litre sold. So they can put more in the 87, and offer ethanol free or very low ethanol fuels at the better AKI ratings. I just really dislike ethanol.

My favourite local fuel is Chevron 94, which is advertised as having no ethanol. It is offered at a very small price premium over the 91, small enough that the increased mileage without ethanol pays for it by a simple energy calculation (if the 91 actually has ethanol; it is labelled as may have, but I haven't tested representative samples, and it can vary by tank load to tank load). What is interesting is that Top Tier says all fuels from a Top Tier supplier must meet the requirements for that supplier to participate, and Chevron Canada is listed as a top Tier supplier. So somebody is offside, not sure who.

No problem with the link, when you look at the Redex product on the manufacturer's web site, they list all of the products (petrol, gasoline, system cleaner, injector cleaner, total cleaner) as having the same composition. It is still a solvent.

I have no idea how to judge diesel fuel quality in Cypress, but would ask a trusted local mechanic where they see there are fuel issues and where they see fewer fuel issues.

I agree that adding ethanol automatically reduces fuel consumption based on energy calculations. Non-ethanol combined with the higher octane would account for the increased mileage. I was wondering if the DME reprogramming that helped BMW's idle and run smoother after 10% became year round in the US, would need to be rolled back to the original version to get the most benefit from a non-oxygenated gas?

Top Tier Gasoline

Canada
Chevron Canada
Esso
Petro-Canada
Shell Canada

Top Tier site doesn't mention requiring 8% ethanol.
Also, TOP TIER gasoline can contain ethanol up to a maximum of 10% by volume. In areas where ethanol is not always used for blending, a TOP TIER gasoline that has passed all performance testing is still qualified as the additive supplier would have tested their product on the appropriate fuel.

The higher octane has zero impact on fuel mileage. No more energy content. And if the fuel has an AKI high enough not to retard timing, anything more is a waste. My best mileage ever in my E53 was on 89 AKI, not 91 or 94 (this was before ethanol contamination).

Read more here:

Top Tier Gasoline

I'm not inclined to run less than 92 in our 4.6. Although, the SkyActiv family runs on 87 with 13:1 compression somehow...(91 minimum for the 14:1 engines)

Like I mentioned, I'll take a look at my intake valves and injectors next time I have the intake manifold off and determine if I should make the switch to Pacific Pride and supplement my own additives every tank...

I've known that using the heater has an impact on mpg, but recently read that using the seat warmers can also impact fuel consumption... Anybody vouch for that? if the fuel light is coming on after 250 miles, I'd start looking at the fuel system cause that's pretty low- even for all city driving..

would need to know the efficiency of the alternator, but let's say you have front and rear heated seats, each pulling 15amps at the high setting? ~200W/seat (@14V). ~800W total. If the alternator was 100% efficient, that is about 1.1HP. even assuming a horrible efficiency of the alternator of maybe 50%, that's 2HP. Same logic goes for the heater, but the heater has even less impact since the fan is the only (large) electrical load. The heater does have an impact on the length of time it takes to heat your engine up to operating temp though.
Which is the main reason for lower mileage in the winter. Longer warmup cycle, meaning the engine is running rich for a longer period of time. Combined with longer warmup times for the oil in the engine, transmission, transfer case, and front and rear differentials. That's alot of sources for increased drivetrain losses due to thicker fluids. Additionally, the cold air isn't ideal for a complete burn, but once warmed up, your O2 sensors account for this and correct it as much as possible.

My first thought was one of the two mileage calculations is incorrect or there are symptoms or codes indicating another cause such as the MAF or a vacuum leak or an O2 sensor. However, this winter is atypical so any outside conditions that are a negative impact on mileage are unusually high.

I think open 'cold' are systems are less effective but they may increase the amount of air getting to the engine. Since an engine is an air pump, more air combined with more fuel should result in some level of increased power. However, the engine must be able use more air than the stock system allows.

I think closed cold air systems are better but I have never read any third party tests for verification. I do notice that serious racers and shops that their income is based on verified performance measurements almost always include a cold air system in the most mild modification packages and the majority are closed air systems. The key there is that air box is part of other mods that need more air to be maximized.

If your engine is not modified and it can't use any more air the only positive result of an any aftermarket air system will be looks and you can hear the air going into the engine better.

The engine increases fuel because the engine is not up to an efficient operating range and cold air is more dense. The colder the weather the longer it takes to reach optimum engine temp. Your system could be extending the time to get the engine to an efficient operating temperature and/or keeping the air colder (more dense) than the stock system.

There are a myriad of normal contributors that are part of a cold weather reduction in mileage, many previously mentioned, that there is nothing you can do except wait for warmer weather.

2 things you can do to increase your gas mileage.
1. park in a heated garage - all fluids will start off at a 'warm' state, so less time to heat up
2. install a block heater - the engine will be 'warm' and won't take as long to heat up, other drivetrain parts still cold though.

One reason I haven't heard yet is rolling resistance. With all the snow we've been getting, that's increased resistance on the X rolling forward, increasing the force needed to push the vehicle...Does the X increase shift points to warm up the engine faster?

rolling resistance would be hard to determine...deep snow, ice, wet roads, dry cold roads...Yes, rolling resistance in snow and rain is higher making your mileage worse. To go with that are the slower speeds you should be travelling at which again are another hit on the mileage.
Also if your traction control is coming on all the time (because you have all seasons and not winter tires) your both wasting gas and brake pads.

No, opposite would occur in slippery conditions, the transmission will shift sooner keeping the RPM's down to prevent excessive wheelspin. Transmission doesn't care what the engine temperature is regarding shift points.
If in (deep) snow, you should have DSC off, *and ideally transmission in Sport or Manual mode :)

*disclaimer, watch out for hidden obstacles under the snow...

I seem to remember that the transmission does shift differently when cold, not due to traction but as part of the transmission control logic. It is related to the heat exchanger using engine coolant to warm the transmission fluid more quickly.

Also don't turn off DSC if you have sufficient throttle response to keep moving. If you are stuck and can't start, fine, but turn it back on as soon as you are in motion.

Interesting calculation. I'd use 80% for the alternator, less 10% on the belt drive.

But if it means 1.5 hp, that is about 5% of the 30 or so hp required to maintain steady state cruising speeds. That's measurable.

In MN I can outright see the MPG difference in all of our cars as they switch the GAS from Summer to Winter. Winter fuel having more originators (sp?) but bottom line is those displace the denser gas, gas being higher in raw BTUs (BTU = energy). Sure there are theories about Winter gas burning cleaner but don't most computers in cars from 92 balance fuel burn factors?


In winter time our e39, X5, Sienna and MX5 all drop 10% right as the gas changes. During the summer time I have also played with buying ethanol free gas in the lightweight MX5 (4-cylinder) see an average of 10% higher MPG with ethanol free there too.

Agree on the prior postings too of tire pressure. Huge drops in tire pressure with the crazy low temps and is something often missed. (air pressure in a tire typically goes down 1-2 pounds for every 10 degrees of temperature change).

Interesting thought on extra electric draw during the winter but would that be offset by massive draw for A/C compressor in the summer?

As for transmission shifting: I have no idea on the transmission programs based on temp but I can tell you my 2005 @ 90k miles is shifting better after replacing my AT Transmission Thermostat (part 20 here RealOEM.com * BMW E53 X5 4.8is MOUNTING PARTS F RADIATOR ) Transmisison is appears to be warming up faster and shifts very smooth again once warm.


some other ideas here via google:
http://www.topspeedracer.com/better-...an-winter.html

speaking of MPG: I wonder how age of oxygen sensors might impact rich cycle warm up time or if this would be increased with older original OX sensors) ?

Anyone know reasonable way to accurately test response times ?

I usually just fill my cars up and drive not really paying attention to my mileage other than what the OBC says.

On my last fill up I reset my trip meter after remembering this thread.

I can't believe it

I filled up with 92 octane Non Oxy 0% Ethanol on my last fill up.
24.xx gallons

292mi. before empty with 7mi. range left according to OBC:wow::thumbdown

NOT COOL

Gas what? You boys should be grateful to be getting what you are. If you
want to know "really bad gas mileage" come over to the range rover club. Just so happens The RRSS that sits next to the X averages between 10.9-11.3mpg for 'normal' (is it possible to drive 510hp economically?!) driving....if you're careful you can knock it into 12mpg but that's more work than fun. It works out to about $80 worth of go juice every 3 or 4 days on average. Seriously, when it's empty...fill it; and when it's cold, fill it some more! If you're MPG conscience don't buy a 5000+lb SAV. Bottom line.

Threads like this just make me chuckle.

OK, for the 4.6is at 70mph and -5C (winter), I get 41.2HP including air drag and rolling resistance. I guessed .015 for winter tire rolling resistance and an optomistic 80% drivetrain efficiency. Have no idea what the engine efficiency is, so stuck with the default of .22, possibly higher on the 4.6?
Used this calculator: Aerodynamic & rolling resistance, power & MPG calculator - EcoModder.com
And used 4.6is data from here: BMW X5 4.6is E53 (2001) - technical specifications - maximum power, maximum torque, fuel consumption - urban/extra urban/combined, maximum speed, acceleration, weight, dimensions, engine, suspension, rims/wheels, tyres, brakes, transmission/gear box,

Still, that's 3.5% going to just seat heating. I plugged in a parasitic load of 800W and it lowered the guesstimated gas mileage from 13.2 to 12.8mpg.

Interesting to see that the difference between -5C and +25C is 8HP because of the lesser air density and lower rolling resistance (summer vs winter tires).

Warning, Overload, hard drive full, too much information to process, drive less, don't check mileage in winter.

I used a SWAG (OK, some judgement involved) for my 30 hp figure. But I wasn't thinking 70 mph; the average on my vehicle over several years is closer to 36 mph, at which speed 30 hp may actually be pretty close. But then I don't have rear seat heaters. The only point was that the 5 or so % is another hit against mileage, added to increased idling time, less engine efficiency when cold, and all the other things that bring mileage down in winter.

What is surprising to me is that we have all these posters who didn't know that their mileage would drop when it got cold out. It has been doing so for the last 100 years or so.

BCR: You have to allow engineers to be engineers every now and then ;)

racing: thanks for that calculator, it is interesting to play with.

I used the 4.6 vehicle figures (weight, cd, frontal area) at 5 c (my temp today) and pushed my average speed up to 40 mph, slightly higher than my average on my vehicle. The variables were:

Vehicle weight: 2180.9 kg / 4808 lbs
Crr: .012
Cd: .35
A: 2.8 m2 / 30 ft2
Fuel energy density (Wh/US gal.): 32970
Engine efficiency: .20
Drivetrain efficiency: .95
Parasitic overhead (Watts): 800
rho: 1.269 kg/m3

I got 11 hp total, lower than I had estimated. At 75 mph (hard to maintain that over a drive cycle) it was 43 hp.

I don't know if 800 watts is a reasonable figure, but taking it on faith I got 7.63 l/100 km and 8.38 l/100 km with an 800 kw parasitic load, at 40 mph, representing a 9.8% fuel consumption penalty for seat heaters on high. That is about double what I had estimated.

I know, but it is sooooo painful.

How do you account for head or tailwinds, air density differences, summer/winter fuel additives, average speed or terrain. Seems like the only way to be close to accurate is for that particular X5 that the formula is based.
What would you say the +- range is for accuracy?

Air density is covered in that link, as well as speeds vs. HP in the result set, and summer/winter fuel energy densities (approx.)

Wind can be averaged out if you drive round trip with approx. the same wind speed/direction. That's why (one of the reasons) they make you drive both directions at Bonneville Salt Flats when doing Speed Week.
Terrain is tricky. My gas mileage in Washington is going to suck compared to someone in Iowa...I suppose you could add in another factor for change in potential energy due to elevation change. Also need to account for combustion efficiency on a NA motor at higher elevations. And the lead foot effect of going uphills.

+- 50% :)

Correct, there are many considerations in the equations to achieve accuracy. It is my understanding that the intention of the calculation is something that can be universally applied for a reasonable difference in mileage one can expect from summer to winter when nothing is wrong with their X5. I stand corrected, +- 50% works for me.

Yes, all X5's being identically maintained, same tires, same gas (meaning station not brand), same highway, will have different MPG because of the foot attached to the accelerator pedal. That's where the +- 50% comes in ;)

On the m62 one, I get 450 Kms for a tank in the winter and 550 kms in the summer but that's most likely due to the traffic in summer not being as slow.
I run with no clutch fan.
I kept an eye on the oil temperature and at -20C outside temp, it barely makes it to the operation temp by the time I get to the office which is about 40 min drive, unless it's heavy traffic.

On my 4.4i ive been doin pretty decent. About 15.5-16 even with a bad ccv and the below freezing temps. LOL

Sharing me experiment but noted it was far from perfectly scientific.
Made a round trip today consistent of 175 miles each way (350 round trip).
Air temps ranged from 9-15F

On the way first leg and half of the return leg gas in tank was from Costco 91 octane. On the return leg I filled up from empty (21.87gallons) of NonOx 91 octane gas.

Mileage numbers using on board computer. Yes I'm sure it has an error factor but just consider this comparison.

At start of return leg I reset consumption average #2 a few times 10-15 miles apart while on the Costco standard winter 91 octane gas. Each time the number floated back to match the consumption 1 field of 15.6mpg.

After filling up with the NonOx 91 Octane I again reset consumption 2 a few times and then left it for the remaining 85 miles home.

I am sure there were lots of other variable factors but I would say foot position on gas pedal and speed were fairly consistent.

NonOx gas was later in the day so air temp was slightly lower (9F vs 12F). No noticeable wind, no real changes in elevation.


Results
(No photo sorry)
Consumption 2 had 70 or so miles on standard winter gas 91 Octane from regular supplier.
= 15.6 mpg

(Photo)
Consumption 2 in picture has 70 miles or so highway on NonOx 91 octane.
= 17.8 mpg


Consumption 1 in photo I reset few days ago. Has 80 mix town highway, + full tank on highway all regular 91 octane, and the 70 or so miles with NonOx. Not super relevant but I'm giving details since it's here.
http://img.tapatalk.com/d/14/02/24/4usy3uba.jpghttp://img.tapatalk.com/d/14/02/24/qabaryve.jpg

Junkcosmos-very interesting!