I assume you have a manual transmission? Which engine do you have?
A huge part of why my mileage is terrible is because I basically have the worst possible commute for fuel mileage. live in Chicago, which supposedly has the worst traffic congestion in the country. My commute is only about 8-10 miles, but there is a lot of variation in speed. I can go from stopped to 65-75 miles an hour back down to stopped several times on my commute. The commute takes about 30 minutes, and I spend a lot of time idling.
Obviously that is a ridiculously low mileage for a car, even given the conditions. My fuel mileage never dips below 18 mpg for an entire tank, but it rarely goes above 20 mpg unless I leave the city. Looking at similar vehicles on Fuelly, I don't think it's that far out of the norm.
My Impreza is a 2010 OBS, with the 2.5L NA EJ25, and a 4EAT. I think what really kills my mileage is the 4-speed automatic. From what I've read, it's absolutely brutal on fuel efficiency compared to the 5 speed manual. The NA uses a lot more fuel than the turbo when just puttering along as a result of its higher compression (10.0:1 vs. 8.2:1) It's not necessarily a negative - my car is faster off the line than the turbo, especially after sitting in traffic on a hot day.
I know the WRX has a DOHC engine, whereas the 2.5i is SOHC. That probably makes some difference in efficiency, though I don't know how much.
On top of that, I almost always have my roof rack on if I'm driving in the city, and I usually have a bike rack mounted as well. Plus, I have the hatchback, which I've heard also impacts mileage, though I have no idea if that's true.
I've also replaced the somewhat narrow stock-all seasons with wider and softer tires summer tires. I run high sidewall winter tires on steel rims in the winter, which weigh a lot more than the stock alloys/all seasons.
Regardless, the Impreza really sucks at city mileage compared to other cars because of the added weight and drivetrain losses of the AWD. (As you probably know) It's really no surprise the 2.5i and 4EAT have been replaced by a much smaller engine coupled to a CVT.
Yes, I had a manual transmission. I assumed your comments regarding "second or third gear" implied you had a manual transmission. Automatics have come a long way in the past few years in terms of fuel mileage, but "slushboxes" like yours are probably the worst. I didn't know the Subaru automatics were that bad. I do know the new 2.0 with a CVT yields good results. It sounds like your driving pattern forces you to be in the worst fuel mileage ever (lots of time idling plus several bursts up to 75? ouch!). I assume you've explored other routes for your commute. Even something where you are driving slowly but not stopped/highway speeds should give a marked improvement.
The hatchback probably doesn't impact your fuel mileage much. I don't think the difference between DOHC and SOHC is going to have any measurable impact on fuel mileage either. Nor would I assume that a compression ratio change does that much. Your final drive ratio is probably the most significant impact. Additionally how much time you spend in "lockup" mode (where the fluid clutch is essentially disengaged and the engine crankshaft is directly connected to the driveline) is a major contributor. The roof rack absolutely impacts fuel mileage as Consumer Reports demonstrated: http://www.consumerreports.org/cro/news/2013/07/tests-show-b...
I use the manumatic function a lot in my 4EAT, because it always seems like it's in the wrong gear otherwise. I test drove a 5 speed and I hated it, cause the gearing seemed horrible for the speed limits which are really common around me.
Anyways, I take the highway to work, and I take a short stint on a highway and then surface streets on my way home. On my way home I run in to something like 40 stop signs. Pretty much every intersection has a four way stop for a few miles of my commute.
I can actually quantify how much the roof rack affects mileage, because I track whether I have it on my car or not in addition to my mileage.
A huge part of why my mileage is terrible is because I basically have the worst possible commute for fuel mileage. live in Chicago, which supposedly has the worst traffic congestion in the country. My commute is only about 8-10 miles, but there is a lot of variation in speed. I can go from stopped to 65-75 miles an hour back down to stopped several times on my commute. The commute takes about 30 minutes, and I spend a lot of time idling.
Obviously that is a ridiculously low mileage for a car, even given the conditions. My fuel mileage never dips below 18 mpg for an entire tank, but it rarely goes above 20 mpg unless I leave the city. Looking at similar vehicles on Fuelly, I don't think it's that far out of the norm.
My Impreza is a 2010 OBS, with the 2.5L NA EJ25, and a 4EAT. I think what really kills my mileage is the 4-speed automatic. From what I've read, it's absolutely brutal on fuel efficiency compared to the 5 speed manual. The NA uses a lot more fuel than the turbo when just puttering along as a result of its higher compression (10.0:1 vs. 8.2:1) It's not necessarily a negative - my car is faster off the line than the turbo, especially after sitting in traffic on a hot day.
I know the WRX has a DOHC engine, whereas the 2.5i is SOHC. That probably makes some difference in efficiency, though I don't know how much.
On top of that, I almost always have my roof rack on if I'm driving in the city, and I usually have a bike rack mounted as well. Plus, I have the hatchback, which I've heard also impacts mileage, though I have no idea if that's true.
I've also replaced the somewhat narrow stock-all seasons with wider and softer tires summer tires. I run high sidewall winter tires on steel rims in the winter, which weigh a lot more than the stock alloys/all seasons.
Regardless, the Impreza really sucks at city mileage compared to other cars because of the added weight and drivetrain losses of the AWD. (As you probably know) It's really no surprise the 2.5i and 4EAT have been replaced by a much smaller engine coupled to a CVT.