so about a month ago i bought a 1998 lx touring edition protege. it has 189km on it and its an automatic 1.8L engine. so after resetting the trip meter to see how far im going every time i fill up, im getting around 10 L/100 km between city and highway combined. this is about 23.5 miles per gallon. i drive very conservatively and i recently had the oil changed, transmission fluid and filter changed, spark plugs changed, and tossed in a fuel injector cleaner. im assuming i should be getting better mileage out of a tiny car like this, so does anyone have advice as to what it could be thats giving me such poor efficiency or what i can do to improve this? thanks

 

O2 sensor maybe

 

23.5 MPG is about right for these cars in normal driving mode. A combination of city and highway driving. I get around 22 MPG in my 1996 ES with 1.8l and ATX. And I've got my foot in it most of the time. It's better for the engine to bring it to it's full power band. I will get around 30 MPG if it's all highway. I will also get about 23 MPG with summer formulated gas and about 21 MPG with winter formulation.

 

that doesnt seem right though...the rated fuel specs im seeing in most places range from 23-26 mpg for city and 30-32 highway. and mine is split about 60/40 city and highway. so youd think id get somewhere around maybe 26 or 27, but im pulling in 23 on the dot, and this is in the summer with conservative driving.

is there any way to tell if the o2 sensors are playing a problem in this, and if so, is this a repair i can do myself? (im very new to cars but want to do as much as i can on my own)

 

Is your "check engine" light on??? If so then you may have a bad sensor. If not then itis working fine.

Don't believe everything you read.Here is how the manufacturer figures out the stated fuel mileage.

1. They find a tire that is good for fuel economy only, not that is good for all around driving, then they inflate it as much as they can, to give it the least amount of rolling resistance.

2. They then remove all excess weight. Some manufacturers even remove the seats, A/C compressor, etc.
3. When they have the EPA testers there, they use a professional driver (who is trained on how to get the best fuel economy) on a closed circuit.

4. They have there engineers find a formulation of fuel that will give the best fuel economy.

Don't forget, this is also the statedratings when the car was new. You've got almost 200K, you can't expect a 10 year old machine to perform the same way it was when new. If that was the case, no one would buy new cars.

Now, if you go down to 15 MPG, then start worrying.