Why does my mileage (mpg) suck so bad???

[turbojustin]

My car used to get 27mpg consistently, no matter how I drove it. Now, I am lucky to get 20mpg, (usually 19mpg). The car is a 97 Legacy wagon with a EJ22. The engine has 80k on it. The car and transmission 230k. It runs great and the check engine light is off. Where should I start? This is killing me.

[StatGSR]

sadly thats pretty much what im getting right now. even today, i drove all freeway for over a 200 miles, and im not really expecting much more than 22. i do have a CEL right now, but im not really convinced that has anything to do with it, since the CEL that im getting is the most retarded vague piece of information i have ever seen.

so for now, im just blaming it on that shitty winter gas that is everywhere.

[LegacyRob]

change your plugs, wires, air filter and o2 sensors

[turbojustin]

sadly thats pretty much what im getting right now. even today, i drove all freeway for over a 200 miles, and im not really expecting much more than 22. i do have a CEL right now, but im not really convinced that has anything to do with it, since the CEL that im getting is the most retarded vague piece of information i have ever seen.

so for now, im just blaming it on that shitty winter gas that is everywhere.

What CEL are you getting? I used to get CELs for fuel pressure sensor/knock sensor, but it went away when I swapped the engine.

[Huffer]

winter gas.

[Wiscon_Mark]

winter gas.

bingo.

Combine that with your car taking longer to warm up (open loop fuel tuning until it warms up which uses a ton of gas) and colder temperatures causing more resistance in the drivetrain (at least that's been my experience with the temps at -10* the last week) and you'll see a dramatic drop.

If it persists into May, you may want to look at a tuneup. But I see a dramatic drop in fuel economy every winter. Not much to do about it.

[w_lred]

I'm getting the same problem. Before, I was easily doing 525km on a full tank.... but now, i just get up to 400km. My mechanic said it could be the winter.... but 125km reduction???? That's tooo much. Anyways, he said it could be that or the temperature sensor. Anyone else know a way to be more 'environmentally friendly'?

[Wiscon_Mark]

Trust me, winter gas does hell on mileage. Then there's the low temps. I don't see what a temp sensor would have to do with mileage...you mean the Mass Airflow Sensor? If that were bad, you'd likely have a CEL.

[sansMYSTi]

I'm getting the same problem. Before, I was easily doing 525km on a full tank.... but now, i just get up to 400km. My mechanic said it could be the winter.... but 125km reduction???? That's tooo much. Anyways, he said it could be that or the temperature sensor. Anyone else know a way to be more 'environmentally friendly'?

Same here - also factor in higher rolling resistance winter tires and usually heavier steel rims (it takes more energy to get heavier wheels to roll, although better coasting should improve economy slightly).

[shizznats]

Just tested my mileage n looks like im getting about 23mpg. not bad.. anywhere from 20 up is what id expect on my engine.

[1-3-2-4]

man that sucks.. I had to rent a car last week to go to N.C and I got 37 MPG from the 07 Kia Optimum.

hell I did a high speed run with a black 07 Sti on the way back and I still got myself 395Miles from the tank when the low fuel light came on as soon as I pulled into my drive way when I got home. (I filled up in a small town in VA)

[sansMYSTi]

Just got 19 mpg with my BH this morning - I was getting between 17 and 19 mpg with the STi :neutral: