Bought my '07 Sonata (used) in March of '08. Do most city driving and getting about 25.5 mpg. Took it on it's first road trip this weekend, and the MPG didn't change AT ALL? Any ideas? I was going 80 mph most of the way (5.5 hour trip).....
Kinda bummed :mellow: javascript:add_smilie(":(")

Did you reset your Average MPG meter before this trip? If not, you didn't get a MPG reading for your highway trip, but rather all the cumulative miles you've driven since the computer was last reset. If you've not reset it, it will be averaging all the miles since whenever the previous owner last reset it. If the previous owner never reset it, you could conceivably be looking at the average of the gas mileage since the car was new. In that case, 5.5 hours (~440) won't mean much in the scope of things, and I wouldn't expect to see a change on the MPG meter with such a trip w/o a reset first.

If you want to see what kind of mileage you're really getting on a trip like that, make SURE to reset the MPG meter when you start your trip!

I thought I did do the reset thing...but I'll double check when I get out of work. I thought maybe is was a dirty air filter or something mechanical. Thanks for responding. :57: :liebe011:

Note: You need to press AND HOLD the reset button down until the MPG display goes to "-- --". Once you see that, then it's reset. Simply pressing it quickly won't reset it.

Just FYI...

from what i have read in other posts you should drop the speed to 65 and you will get better MPG...

as everyone else has said, reset your MPG computer.. but if you really want to know, do a manual calculation..

80 MPH will severely drop your mileage, even on the I4.. i have been driving 95% highway since I bought my V6 and my summertime MPG's is in between 28-30 MPG's (last tank was 28.6, the tank before was 30.5).. but i put my cruise on 70 (ish) as much as possible

True way to check your mileage is to fill up before a trip... 3 clicks on the pumper and then fill up after the trip with the same 3 clicks on the pumper. Then just take your miles and divide it by how many gallons you used.

So far the on board computer seems accurate, but I only have 1 full tank to compare.

To increase mileage I've found that going uphills don't push the car too much to maintain the speed. Downhills I keep the same throttle input (end up speeding) and use the momentum to coast if it's flat or take me as far up the hill before having to give it some gas.

Also... keep in mind.... The thing what kills mileage is braking!

FWIW I did a 295 mile trip to Vancouver and back - 85% highway / A/C on most of the time and 1hr and 15mins idling at the customs border and I got 31 MPG (9.45 gals used). I drove between 60-75 varying speeds +/- 2mph as I'm still in the break in period. Car is still new and breaking in (400 miles when I took the trip) so I figure that may increase a little bit given the same conditions.

This post has been edited by rsjyss: Jul 24 2008, 09:24 AM

rsjyss, 2 clicks on the pump spews gas all over the side of my car :P

I fuel up at the same station all the time, and use the same pump. Fill till it clicks and shut it down.

25mpg is pretty low for a V6 on the highway, even at 80 mph, but the previous posters are right, 70 mph will give you MUCH better mileage. Cracking 30 isn't too hard in light traffic on flat terrain.

At 70 mph I can do 30ish in moderate to heavy traffic going up a mountain with copious use of cruise control and avoiding the brakes whenever possible. :D

what's even worse is that the original poster has an I4... but you're right, 25 MPG if you are truly doing highway driving (constant speed, cruise control, etc) even for a V6 seems like it is a bit low...i would think it could be more like 27ish...

rsjyss- i find it slightly hard to believe that you got 31 MPG in a V6 while spending 1.25 hours sitting in line going nowhere with the a/c on... those numbers seem EXTREMELY high...

LOL, I didn't even notice that it was an I4.

I understand where the OP is coming from now, OUCH!

CJohnston must be right.

25.5 mpg for city driving it too good. 25.5 for pure highway driving is well below normal (unless you drive like a nut case).

So CJohnston is probably right, the 25.5 average is so OLD, that nothing would change it anymore....

Once you reset it, then you start fresh, and you'll see city driving LESS than 25.5, while highway driving (reset it again!) would go far beyond 25.5.... Posters here are getting 32-33 easy on their I4 Sonatas. 35-36 if one really drives conservatively....

I have the V6 and with my mixed driving City and Highway. This thing loves to sit at 23 mpg. However one trip with mostly highway driving at 65 mph. I did reach a solid 33.7 mpg (based on the trip computer which has been almost perfect for 8 fill ups now), until I reached DC and continued another 100 miles with mixed driving dropped to 27mpg. by tthe time I had to fill up.

I am traveling to Atlantic city this weekend with a stop over in Philly. I hope to get an average of 28mpg this trip.

for normal highway driving, 27-30 is about right for the V6 (in warm weather of course).. you can get over 30 once in a while, but it wont stay there...

but i have noticed my trip PC is never spot on anymore.. (i reset with each tank).. its normally 1 MPG off.. (either way).. when i filled up yesterday, my trip PC said I had 29.5 MPG, but my real mileage was 28.6 when i did my manual calculation... on a previous tank, my trip PC said i had 30.3 MPG when my real mileage was 28.7 MPG.. but then i get 30.4 on the PC and i will end up with 30.5 real MPG's.. so its a "sometimes, sometimes not" thing for me...

but as Mama has said, you need to reset the Trip PC... my wife's Tucson was stuck on 19.8 MPG no matter how she drove (she never reset it), but i did a calculation for her, and she was closer to 23 MPG....

Went out on my lunch hour and tried it....it worked...thanks so much! I love this chat forum, very valuable. Thanks again. :460: :460: :460: :460: :460: :460: :460:

.... Now you need to repeat your 5.5 hour trip again.

When I run 80-85 I get (manual checked) 28-29 MPG.

heh, if i ran 80-85, im guessing i would be down to 25 or 26 (but then I have a V6)