I know I started driving with somewhat of a lead foot (AWD allows for it hehe), but with a wife that's easily made car sick (and two dogs usually trying to stand up half the time), I've long since adapted, and now most would consider my driving to be quite reserved, especially in transitions of both speed and direction.
I buy high mileage Subarus, one thing that consistently effects all of them is sludge buildup in the intake manifold from the PCV, the crankcase venting oil into the intake. Also the carbon from the valves eventually start constricting the intake also. The valves get loaded with crap too. Also poor fuel, un-combusted gas, oil vapors, etc start clogging up the cat converters. Old wheel bearings don't help either. There are bottles of cat converter cleaner you can get that might help, also taking off the intake manifold and cleaning it out helps. Personally I dump seafoam down the spark plug holes, pour it down every intake port, etc and let it sit over night. I leave the spark plugs out and I crank it over so it sprays all that stuff out and it's nasty. Makes a mess but it's worth it. Do it outside if you try, and before oil change. Also right before an oil change, add some sea foam or block cleaning additive and let it idle for a few minutes before you change the oil. That cleans all the sludge out of the block. K&n air filters work nice, clean your mass airflow sensor with mass airflow sensor cleaner. In most importantly, switch to full synthetic oil if you haven't already. Also replace the oil in the differentials with full synthetic. Higher performance spark plugs work nice too. Sometimes new 02 sensors help, depending. If you do all that, you're going to feel a tremendous difference in torque and power, most of all, gas mileage will be up again. Might even be better than your original gas mileage at low miles.
I’m going to have to try this at my next oil change. Right now I average 20mpg and I don’t think I’ve gotten above 22 since owning (bought at 145k). I put in a new Pcv valve and cleaned the throttle body so far..
Compression test if you can, I'm about to do this 2012 outback 6mt I just picked up 2 days ago, I'm going to do everything I mentioned above on this one now. I'm noticing a lot of sag in the ass when I shift gears. I bought cheap strut stabilizers that spread the struts and makes suspension tighter. That might help with getting more torque to the wheels instead of suspension absorbing some of the energy. (Theory of mine). I'm getting 20mpg and it's throwing a code for p134 front 02 I think, I got one ordered. I'm going to see if I can get in the ECU with my tactrix and datalog, check AVLS, etc, maybe advance timing a little, Subaru is very conservative but this is dangerous. good luck with yours as well 💯👌
That's OK for highway. What about big city driving. Stop and go, stop and go?I get 16mpg in winter. In summer time about 18-19mpg.On highway around 26-28mpg depends how fast I go. And I love it. Very good car
213k now still doing great
About 23 MPG in city & 18 MPG in country in my 2012 Subaru Outback 3.6 R. But fuel is a variable expense, the less I drive the less I spend
181K on my 3.6R and I know I can tell a difference between the (now way more expensive) ethanol-free fuel and the normal E10 gasoline (also beware there's now stations selling what they call "regular" fuel 88 octane that is actually E15 unlike the actually-normal gas most places sell as E10)
