I have a 2004 wrx wagon, only mods are 17in superleggeras, samco y-pipe and blitz cat back. My gas mileage sucks. I only get about 20-21 mpg. I don't race it, or drive that fast, usually only 70-75 on the freeway and always at the speed limit on city streets. During the course of a normal gas tank, I would make 5-6 WOT pulls in 3rd or 4th gear while getting on the freeway. I drive about 75% freeway and 25% city and still only get 21 mpg.

Could the few WOT pulls cause such bad gas mileage? I drove to SF this weekend on a full tank of gas, and I'm already at 1/4 of the tank left, and I've only driven 200 miles, all freeway.

Any help or recomendations would be appreciated.

Tim

 

Yes, going WOT will kill your milage. Last tank I filled up, I got 240 miles until the gas light went on...I seem to always be on boost.

 

try not getting on WOT when entering freeways. i stopped doing it for a couple tanks, and i actually noticed a differnce. before i also only got 20-21 mpg. when i do not go WOT on the freeway i get about 23-24..which all adds up

 

I will try it with my next tank of gas. But damn, What's the point of a turbo if you don't get to hear it spool:

 

how many miles are on the car?

have you done your routine maintenance?

plugs, air filter, fuel filter, oil.

are the tires properly inflated?

are you carrying around a bunch of dead weight in the car?

 

god, 20-21, id kill for that gas mileage...I get 17 if im lucky and i always drive nice... I get about 290-300 on the freeway with cruise control on for the whole tank thats like 20 mpg with smooth freway traffic... god damnit

 

I've always got about 20-21 mpg. But when I jsut purchased my 2nd wrx wagon I got 26 mpg several times on the 2600mi trip back to Oregon from TX. I really didn't drive dirfferently (set at max cruise :-) but the elevation changes from the east side of NM to the center of AZ was significant.
What do the folks at high elevation get for mpg?? I was thinking that this is why I got 340 mi before the fuel light turned on!

 

Your poor fuel economy is due to the way you drive, unfortunately. If you wanna play, you gotta pay.

When you call upon the engine to make boosted power, it uses the appropriate amount of fuel and air to generate that power. How you drive can make a huge difference in your vehicle gas mileage, along with other variables such as the terrain, urban traffic, multiple short trips to the convenience store where the engine barely has time to come up to operating temperature (oil temp, not water temp).

I normally average 22 to 24 mpg around town in mild traffic. On the open road on flat terrain I can get 27 to 28 mpg with an all-time best calculated fuel economy of just over 30 mpg when I kept the speed down to 60 - 65 mph. With that sort of driving, I could've easily gone well over 400 miles on a single tank of gas! It isn't practical to drive that way most of the time, especially if there is any sort of traffic on the road - you'll end up being a slow-moving obstacle to traffic overtaking you from the rear and might even be cited for going TOO slow if you pose a hazard to other drivers (the posted limit on this stretch of highway was 70 mph but there was little or no traffic).

Conversely, at the track (road course) my car went through a tank of gas like there was a small hole in the gas tank. With a lot of time spent under boost I'm going to guess that my fuel economy was down to about 10 to 12 mpg. I wish I'd saved all of the gas receipts and noted the odometer readings for the day so I could have calculated the precise numbers.

--
0==WW==0
"…axles of evil…" - george w. bush

 

This is one of the only threads that makes me glad that i bought an RS. I like 30mpg highway.

 

ok so whats my problem, I know it isnt my driving habbits, when I go on a trip on a flat as a pancake road with cruise control on 70mph I get 280 miles on a tank of premium gas... so it isnt ALL about how you drive, my previous WRX got 350-400 on a tank and 260-300 with my having fun all the time, I dont even drive my car hard because I cant afford SUV gas mileage and I know there is something wrong because im not driving a ford excursion.

and no im not filling up at 1/4 tank, I run my car till the gas gauge is below the empty line, and I usualy fill my car at the pump with as much the tank holds according to the user manual...

 

you know ive been noticing this as well on my 06.

now the first tank when i got it. understandably i got horrible mileage cause i had an entire day of slogging the car around back mountain roads. ok thats fine. i payed to play .

second tank. started out awesome had 100miles on 1/4 tank then i got stuck in the middle of possibly the worst traffic jam ive ever been in. it took me over 2 hours to go less than 70 miles.

now. im on my 3rd tank ( mind you i havent even owned the car a week yet! lol ) and im noticing OK mileage. got about 118 miles on a 1/4 so far.

just for my future reference - it is actually advised to drain the car to absolute empty before a fillup? and when i do fillup i only hit about 12gal. max, how much do you guys hit?

 

Some people suggest that you don't wait till it hits empty because stuff could collect at the bottom of your tank.

The most I ever put in the car was 14.2 gal. This is when the pump shut off, I never top off.

 

If you've previously owned a WRX then I don't know what you drive now. If it's a 2.5 liter WRX or STi then the figures will likely be lower than the 2.0 liter WRX. If you have another 2.0 liter WRX and you don't drive any differently, then look for mechanical problems. It's hard to diagnose over the internet.

Also, for those who are GUESStimating their gas mileage by the tankful or the gas gauge, use a calculator and figure out the more precise figure by always filling the tank to automatic pump shutoff, then dividing miles travelled since last fillup by the number of gallons pumped. The Impreza gas gauge display is non-linear and even on one car there could be a difference of + or - a gallon if the car happens to be on a very slight incline when viewing. Don't guess if you have any concerns about fuel economy.

--
0==WW==0
"…axles of evil…" - george w. bush`

 

Do you have an ECU tune? Sometimes an ECU tune will help with gas mileage. Also, how much do those Superleggeras weigh? Unsprung weight will most definitely take a toll on gas mileage.