New to anything Subaru. Bought this car for my son, 95 Legacy,130Kmi. Runs and looks good but at 12 mpg this must have room for improvment. Ck. eng. light is on went to two diff. shops both say it is anti knock sensor. I Changed out the plugs, wires, and air filter. Seems to run great, starts great.
One more ? at 60mph the tach reads 3ooorpm is this normal?
Thanks any help will be appreciated.
Neil in South Dakota

 

3000rpm at about 60mph on an automatic is a bit high, sounds more like youre in 3rd gear. Make sure that the shift lever is in D instead of 3 (sometimes mine looks like its in D but it just needs a tap). Also, when cold the transmission will stay in 3rd gear until warmed up.

Reset the ECU (unplug the positive battery terminal for half an hour or so) and see if the code comes back. If it does then Id suggest changing the knock sensor if thats what the CEL is saying. Another bad gas culprit is the front Oxygen sensor. Youre supposed to get 21-27mpg

Up the air pressure in the tires too. The suggested 30/28 is pretty low. I run my tires at around 38-36 (some people even suggest setting it 2 psi lower than the maximum tire psi, which is listed on the tire) Also, in the cold weather I switch to 5w30 oil, which is a bit thinner and makes the engines job easier when starting.

General fluid changes cant hurt, but I suspect your main cluprit is the cause of that CEL

 

I see this (front oxy sensor) mentioned, is that to say there is a rear sensor? I know it may be a stupid ? but I don't know. Hell I fix furnaces not cars but I do know a little and more improtainly I know what I don't know. I do have people that can help but no Subaru dealers within a hundered miles of the house. I disconnected the batt. will get into it after the bike races. Thanks

 

OK picked up a manual on the car. Put batt. cable back on and the engine light stays out now, thanks. I see there are two oxy sensors. Is it always the front sensor and are they the same part? There are so many sensors on this thing I think it should go to a shop, as changing out sensors till I find it could cost more than I spent on the car in the first place.

 

well hopefully clearing that CEL will solve your problem. my 95 L AWD wagon averages about 21-22 mpg, so you should probably be getting about the same on that car. the only time i really had problems with my motor is when i accidently disconnected a vacuum line (which i didn't even know was there!) while i was installing an intake hose. that cause all kinds of problems, but reconnecting the line and resetting the ECU (it's quicker to just disconnect the negative cable for 5 minutes, then restart the motor after you reconnect the cable) solves that real quick.

 

I dont know if theres a difference between the front and rear oxygen sensor, but the rear is more of a confirmation sensor to make sure the front is working correctly. usualyl its the front that goes bad

 

The rear is a simpler sensor, different part number, and should be cheaper.

 

After resetting the engine light the boy seems to think it is doing much better, will fill it up in a day or two and let you know.