Poor Fuel Economy

[Don67]

QUOTE (Ken B @ Dec 27 2010, 12:28 PM)

I'm wondering how much break-in has to do with this also. EPA site says 3-5k miles for break-in; I just hit 3k so hopefully things will improve.

The only effect the break-in period had on my Santa Fe's fuel economy was to give me time to get used to it. :P

[majbach]

QUOTE (macken @ Dec 25 2010, 11:33 PM)

I don't get a chance to drive this suv/crossover much but I just did a trip up north that was about 80% hiway(half interstate half two lane) and 20% city about 404 miles total (around 880lbs in the car) 77 mph for Interstate type of hiway 62 mph on two lane hiway and 35 mph through the towns It's the 3.5 V6 front wheel drive no roof racks avg temp was 19.4 fahrenheit and my average fuel mileage was 22.8 mpg ....I converted all that for you yanks merry christmas

I wonder how much difference the roof racks make? I have them but never use them.

The biggest factor influencing mileage in my opinion (I take frequent long trips over a variety of terrain and climates), is temperature and surface conditions.
Surprisingly, the colder the air, the poorer the mileage. This is an observation I have made on several trips where OAT varied from +10C to -40C over the course of 600 kms. Mileage went from 10 l/100km to 13 l/100 km on highway. Even at the slowest reasonable speed on the highway, I cannot coax the SF to get better than 11.1 l/100 km highway when the air is below - 35 C. City mileage in that temp can be as high as 15 l/100, the same as what i get in the summer hauling a 2500 pound boat.


Pavement makes a huge difference too. The sealed surface asphalt of the NWT has a course texture to it. When I cross into Alberta where the pavement s smoother, my mileage can increase by 20%. However, throw some snow or slush into that and you're much worse off. I now live in BC, Canada, and even when the air is warmer, all these freakin boulders they put on the highway that do NOTHING but put stone chips in your windshield also seem to have a noticeable adverse affect on mileage.

[Don67]

QUOTE (MajBach @ Dec 28 2010, 03:16 AM)

I wonder how much difference the roof racks make? I have them but never use them.

They make a surprising difference, according to some: http://ecomodder.com/forum/showthread.php/...penalty-96.html

[majbach]

QUOTE (Don67 @ Dec 28 2010, 07:19 AM)

They make a surprising difference, according to some: http://ecomodder.com/forum/showthread.php/...penalty-96.html

Methinks I am about to conduct an experiment.

[bnelsonr]

QUOTE (Don67 @ Dec 28 2010, 08:19 AM)

They make a surprising difference, according to some: http://ecomodder.com/forum/showthread.php/...penalty-96.html

I am sure the roof cross rails make some difference in MPG but the ones on my 09 Santa Fe have slim edges. The ones on the refereed to site are straight up and bulky. Its hard to do good comparisons when things aren't equal.

[majbach]

QUOTE (bnelsonr @ Dec 28 2010, 10:28 AM)

I am sure the roof cross rails make some difference in MPG but the ones on my 09 Santa Fe have slim edges. The ones on the refereed to site are straight up and bulky. Its hard to do good comparisons when things aren't equal.

I am forced to agree. I just took a look at them for the first time from an aerodynamic perspective. There is no way those contribute 10% to the mileage. If they do, the side view mirrors must me horrible.

[kbair]

QUOTE (MajBach @ Dec 28 2010, 11:30 AM)

I am forced to agree. I just took a look at them for the first time from an aerodynamic perspective. There is no way those contribute 10% to the mileage. If they do, the side view mirrors must me horrible.

Probably not anywhere near 10%, but even a little bit can make a difference. I'm referring mainly to the crossrails, and I plan on doing the experiment when it warms up a bit. I'd probably only use them rarely (if at all) and there's no reason to keep them on if they are hurting the mileage. For example, if taking them off saves 1%, with my current mpg, miles driven, and gas prices, I'd save over $39 per year.

[lovemysantafe]

You want to talk fanatical about hypermiling? You should go read some of the chatter that goes on in the Prius forums; talk about some MPG OCD. Somebody with a Prius V (top-line with the bigger wheels) was looking for super-light aftermarket wheels because he found out the stock wheels weighed 25 pounds each.

[akeene]

Hi All,

Great thread, here are my 2 bits to add, I have just under 3000 kms on my '10 santa fe 3.5V6 FWD. My average fuel economy seems to be 10-10.5l/100kms combined 50/50 city/highway driving. To attain these values i am having to be a throttle scrooge. Easy on the accelerator, light on the brakes, and timing my acceleration for hills prior to getting to hills. IMO, I am somewhat obsessed to see how good I can get the mileage. My hope is that this mileage will improve somewhat. Last fill-up was $64.00 (57.7 litres) and 572 kms. I don't think real world driving will ever give the Transport Canada fuel efficiency ratings. But I think the v6 is the best engine choice if you stay light on the accelerator. I believe the 4 cylinder (smaller displacement) has to rev higher and the fact both the 4 and 6 have the same 6 speed negates that benefit. Both engines seem to be very comparable fuel economy wise. The four needs more revs and the six more displacement. So I'd get the six, be mindful of the gas pedal and have the extra power when needed. These are just my opinions I could be wrong. To those who have had their santa fe's for a while how much did your fuel economy improve after break-in period?

Andrew

[kbair]

QUOTE (akeene @ Dec 28 2010, 11:06 PM)

Hi All,

Great thread, here are my 2 bits to add, I have just under 3000 kms on my '10 santa fe 3.5V6 FWD. My average fuel economy seems to be 10-10.5l/100kms combined 50/50 city/highway driving. To attain these values i am having to be a throttle scrooge. Easy on the accelerator, light on the brakes, and timing my acceleration for hills prior to getting to hills. IMO, I am somewhat obsessed to see how good I can get the mileage. My hope is that this mileage will improve somewhat. Last fill-up was $64.00 (57.7 litres) and 572 kms. I don't think real world driving will ever give the Transport Canada fuel efficiency ratings. But I think the v6 is the best engine choice if you stay light on the accelerator. I believe the 4 cylinder (smaller displacement) has to rev higher and the fact both the 4 and 6 have the same 6 speed negates that benefit. Both engines seem to be very comparable fuel economy wise. The four needs more revs and the six more displacement. So I'd get the six, be mindful of the gas pedal and have the extra power when needed. These are just my opinions I could be wrong. To those who have had their santa fe's for a while how much did your fuel economy improve after break-in period?

Andrew

While I understand the revs vs displacement issue, I'm still not convinced that the bigger engine is more fuel efficient. Let's start with the unrealistic EPA ratings - the smaller engine has a slight edge. While we may not always obtain them, I do agree that they are good for comparing one vehicle to the next. I haven't looked at their exact testing procedure, but I'm guessing controlled environment (humidity, temp, indoors), multiple trials, computer controlled acceleration/deceleration, maybe even multiple samples. I'd love to see some of raw data though...

I'm also becoming obsessed with this too, it sure makes driving more fun.