davidschaffer Posted December 21, 2014 Share Posted December 21, 2014 Our recently purchased 99 outback with a 2.2 from a 98 impreza is averaging around 18.5mgp. What gives? I was hoping for low to mid 20's. Is this normal? Anything I can do to improve the mpg? Thanks Quote Link to comment Share on other sites More sharing options...
nipper Posted December 21, 2014 Share Posted December 21, 2014 Give it several tanks of fuel to make sure the number is right. Also winter will kill gas mileage because its well winter. Make sure the car has a thermostat in it and that it is operating. Do you have a lot of stop signs or short trips? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted December 21, 2014 Share Posted December 21, 2014 is the check engine light on? tune up items - plugs, wires, air filter +1 what type of driving: 1. what kind of average speed?2. stop and go/city driving? 3. how far are your average trips? check brake caliper slide pins. Quote Link to comment Share on other sites More sharing options...
davidschaffer Posted December 21, 2014 Author Share Posted December 21, 2014 Give it several tanks of fuel to make sure the number is right. Also winter will kill gas mileage because its well winter. Make sure the car has a thermostat in it and that it is operating. Do you have a lot of stop signs or short trips? is the check engine light on? tune up items - plugs, wires, air filter +1 what type of driving: 1. what kind of average speed? 2. stop and go/city driving? 3. how far are your average trips? check brake caliper slide pins. All of the above lead me to believe this is normal mpg's. It is winter, the drives are rarley more then a few miles. Not really "city" driving but a few hills and stop signs. The wires look new but I'm not sure of the plugs. No check engine light. I thought these cars got around 20-28. Sounds like that may not be the case. Also, last night I noticed that the tranny would sometimes change gears while I was driving in the 55-60mph range. Like it couldn't decided which gear was best for the mph. Is is normal or a sign of a tranny issue. Thanks Quote Link to comment Share on other sites More sharing options...
nipper Posted December 21, 2014 Share Posted December 21, 2014 I live in a land where ever block that has 10 - 12 homes on it has a stop sign. This knocks down my MPG to 13-14 on short trips to the store. This is actually typical for any car or truck as MPG tests are done in lab conditions and n ot 30 40 degrees or less with cold tires and cold fluids. After a few miles once the car warms up the MPG will pick up likr an extented trip. But uou have diff cluid, wheel bearing grease, engine oil, tranny fluid PS fluid all have to warm up, including tires. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted December 21, 2014 Share Posted December 21, 2014 Short trips especially in the winter will really kill it. My '94 2.2L AT to drive 35 miles in 12 short trips during the work week takes about 2.6 gallons so that's about 13.5 mpg. On longer trips it gets around 24 mpg. Remember too winter blend fuel doesn't have as much energy density as normal blend so that can cut it a bit too. And of course all the tune up and other factors already mentioned above. Quote Link to comment Share on other sites More sharing options...
guzzijohn Posted December 21, 2014 Share Posted December 21, 2014 My '99 L wagon 5spd has gotten 34-Summer/hwy but 25 avg in cold. That said we have 2 2.2 Camrys. My wife's '99 suto averages 25(commuting hwy) this time of year. My '95(5spd) gets 31 and 37+ in warm weather. Small engines w auto in Winter are worst case scenerio in the cold. It takes a long time to get all the fluids up to nominal temps and uses fuel to do that. That little engine is hauling a heavy 4wd w a slush box. Wait 'til Summer and see what you get. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted December 21, 2014 Share Posted December 21, 2014 All of the above lead me to believe this is normal mpg's. It is winter, the drives are rarley more then a few miles. Not really "city" driving but a few hills and stop signs. The wires look new but I'm not sure of the plugs. No check engine light. I thought these cars got around 20-28. Sounds like that may not be the case. Also, last night I noticed that the tranny would sometimes change gears while I was driving in the 55-60mph range. Like it couldn't decided which gear was best for the mph. Is is normal or a sign of a tranny issue. Thanks 18-20, in a Michigan winter is about right. You'll likelly get 20+ in summer. With an automatic and the low gears in the forrester trans.....Yopu won't get much better than that. The trans hunting around is because it's trans mapping is set for a 160+ hp engine, and now has to work with only about 130~140 hp. When it should have enough torque to run low rpms in 4th it actually can't.......I would suggest dropping the shifter to 3rd when it's doing this. Automatics suck up the gas and power......espescially in a low HP engine.........Our H6 outback gets better mileage than any other Automatic subaru we've owned........I think because it's always running below 2500 rpms with all the low end torque. 1 Quote Link to comment Share on other sites More sharing options...
Bushwick Posted December 22, 2014 Share Posted December 22, 2014 Might be worth it to install a new air filter, new fuel filter,and replace BOTH O2 sensors. Rockauto dot com has the best prices for O2 sensors. Just because it had a 2.2L transplant, doesn't mean they went out of their way to install all new stuff. Also, check all 4 tires air pressure. Low tires will destroy the MPG. They can be 20psi lower than they are supposed to be and "appear" to still have air in them. Do all that and I'll bet your MPG will improve. The trans "hunting" in OD can actually be the torque converter clutch failing. If you are on a perfectly straight section of road with no hills/dips and it's doing it there, suspect the converter clutch. Quote Link to comment Share on other sites More sharing options...
pginter96 Posted December 24, 2014 Share Posted December 24, 2014 +1 to everything mentioned above, especially cold weather and slushboxes. also consider if brakes are hanging up, extra wind resistance such as roof racks, etc. UPSTREAM O2 SENSOR and/or exhaust leaks. may not throw codes, but O2 sensors can become restricted with age and make a less-than-optimal data point for the ecu to tune the engine to. As I will (hopefully) be joining you in the EJ22 swap club soon, keep in mind that this car was set up for a 2.5. Not entirely sure, but this could mean different gearing and such. If its an outback limited, its worse as you'll have heavy heated leather seats and maybe heavy sunroofs to add to the weight you're hauling around. While the 2.2 is smaller and more efficient, it is also less powerful so the mpg's may suffer. overall, I have heard that mpg of the 2.5 and 2.2 swap should equal out. With any luck, Ill find out for myself soon. Quote Link to comment Share on other sites More sharing options...
Bushwick Posted December 24, 2014 Share Posted December 24, 2014 4.44's will eat more gas than 4.10's. BOTH however are not economy gears by any standard. Maybe an 8 speed auto or a 6-speed manual can tolerate them, but not a 4 speed auto. If you want better MPG with a slight loss in off the line acceleration, find something with gearing below a 4.10. Highway MPG will increase greatly. In lieu of a front/rear gear "downgrade", you can stick over-sized tires on (taller tires) and it'll do the same thing. Dunno the max tire height that safely fits, but increasing the tire height by 2" will be very noticeable and your cruising RPM will drop at highway speeds. If you are in a LOT of snow, that extra tire height will actually assist in getting unstuck since it won't be as easy to spin the tires. Quote Link to comment Share on other sites More sharing options...
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