Dwardo - Everything in Nova's response is 100% correct. Probably the tire pressure is one of the most critical elements for 'good' fuel economy. I run my Touring at 35 psi and check it often. The dash computer is not accurate enough to obtain reasonable economy numbers. Paper and pencil required!

If I were driving at approximately 75 MPH (your 119 km/hour) and got 24 MPG (your 9.4L/100km) I wouldn't be too disappointed. Tourings are not exactly streamlined.

60 MPH (~100 km/hr) would add about 7 minutes to your commute time and would help make for an improved fuel economy situation. 2500/2600 RPM is a reasonably good highway fuel economy engine speed.

You didn't mention transmissions so I'll assume you have a manual.

It's very difficult to compare two different cars for economy. My 2200 pound Corolla gets about 38/39 MPG compared to my wife's 3000 pound Touring at 33/34 MPG - driving exactly the same highway trip. Both at steady 60 mph (100 km/hr).

Ray

 

VegasRay and NovaResource thanks for your responses:

My tires pressure is good. I also have nitrogen in the tires to help that. I know the Touring is a bit bigger and heavier then my Sentra but on paper, the Touring got better fuel mileage and is 10 years newer which I figured technology vastly improved. I just figured driving the vehicles the same way, I would get better mileage with the Touring.

I know the computer isn't accruate but all I know is I got 500 KM out of 42 L tank on my Sentra and I can't get that with a 53 L tank on the Touring. I havn't been resetting my fuel economy reading at every fill-up but my main tracking mechanism is how many KM's I get per tank which is only about 480 km.

I know by slowing down I could vastly improve fuel economy but I was trying to compare the two vehicles and keep as much things as I can constant.

I drive an automatic by the way.

Thanks

 

And again, you can't compate a larger, heavier, less aerodynamic car to a smaller, lighter one. Yes, technology has improved but physics doesn't change. The larger and heavier the car, the more higher speeds will affect the fuel economy. My advice, slow down or buy a smaller car.

 

Not to nit-pick or anything, but the Touring actually has a slightly lower drag coefficient than the Sentra....so aerodynamics shouldn't really be a factor for it's higher fuel consumption. Weight and poorly chosen gearing and final drive ratio (especially on the automatic) would probably be more of an issue....

And keeping it at 2500RPM or 100km/h (60mph) would be OK if the flow of traffic on the highway wasn't substantially faster. Nobody likes being the slowest vehicle on the highway, unless you're driving a Prius or a Smart.....

 

And where are you getting these numbers?

2001 Sentra (source):
- height = 55.5"
- width = 67.3"

2011 Touring (source):
- height = 59.8"
- width = 69.5"

Now, you tell me how a car that is 4.3" taller and 2.2" wider has a LOWER drag coefficient? Granted, size is not all that drag is based on but the cars are similarly shaped in the front with the Touring having a roof rack and a wagon rear shape. I still don't see how the Sentra could have a higher drag coefficient. Point me to some source for your numbers otherwise, I don't buy it.

Driving fast just because everyone else is, is stupid and wasteful. If you want to drive fast then you can't complain about bad fuel economy.

 

Sorry, I was comparing 2010s. Actually, according to Cars.com ( http://www.cars.com/go/crp/index.jsp ) the 2011 Touring and the 2001 Sentra both have a drag coefficient of 0.33. So pretty much equal there. Not quite sure as to why you are quoting height and width as they are NOT used to determine drag coefficient, depends more on the overall shape of the car. Also, very few Tourings that I've seen on the road actually have roof racks. Mine certainly doesn't. And a wagon/hatchback rear end does not have to be a huge detriment to aerodynamics....just as an example, the VW Jetta sedan and wagon are nearly identical in terms of drag.

Anyways, I still don't think that aerodynamics should be a major point in this particular comparison.

OK, we're not talking about racing or jackrabbit starts here....just steady cruising at a slightly higher speed. Over 2500RPM the Touring's economy just seems to do a nosedive... Hyundai seems to have really messed up with the gearing on this thing.

 

I find that hard to believe that the Touring with a roof rack is a clean through the air as the Sentra. Maybe that drag number is on a Touring sans roof rack. Regardless. The Touring is over 340 pounds more than teh sentra with a larger engine.

All cars do that, not just the Touring. Fuel economy drops drastically above 55-mph no matter what car you drive. Again, if you want to save fuel, slow down. If you want to speed, then don't complain about fuel economy. You can't have it both ways.

 

I know there are alot of factors that affect fuel economy, but was I wrong to think I would get better fuel economy based on these numbers?

2001 Nissan Sentra City - 23 MPG \ 10L-100km Hgwy - 30 MPG \ 8L-100km
2011 Hyundai Touring City - 32 MPG \ 8.7L-100km Hgwy - 43 MPG \ 6.5L-100km

Was I wrong to think if I drive both vehicles the same way, I would get better fuel economy on the Touring? If drag, weight, aerodynamics and all the other things you guys are talking about affect the fuel economy so much, then why wouldn't it factor in a little bit on the estimated fuel economy numbers?

Was I wrong to think my 2011 Touring would save me gas money over my 2001 Sentra? This is my argument. I just feel like I was mislead or there is something wrong with computers on my car.

 

Those numbers can't be correct. The Touring does not get 32-mpg city and 43-mpg highway. Here are the actual numbers:

2011 Touring automatic (source):
City - 23 MPG (10L-100km) & Highway - 30 MPG (8L-100km)
http://www.hyundaiusa.com/elantra-to...fications.aspx

 

OK, those numbers sound a LOT more reasonable. They're within about 1l/100km of what I'm getting. I could accept that considering my slightly more aggressive driving style.

Unfortunately, Natural Resources Canada, who provide the official government fuel economy figures show a MUCH lower consumption. They're rating the auto Touring at 8.7l (32mpg) city, and 6.5l (43mpg) highway. Even with the slightly bigger Imperial Gallon that Canada uses for their mpg.....it just don't make sense...

http://oee.nrcan.gc.ca/transportatio...s.cfm?id=79385

So you can see where some of the confusion is coming from, since many people buying a car in Canada use the government website as a comparison tool. And I would love to see HOW exactly they came up with those rediculous numbers.....