I purchased a used 2000 Forester L back in May, 2003.

While I'm happy with car car itself I am very unhappy with the MPG that I've been getting. I am getting about 14 MPG in city driving. At my last oil change at about 30,000 miles I replaced the fuel filter among other things. In few weeks I am going in for a tune-up, air filter change and PVC replacement. Can anyone come up with some other ideas to improve the MPG ?

 

~Howard

Shy of really minor things like drive downhill all of the time and keep it waxed and clean, you've hit the highlights. MPG does seem to be one of the major disadvantages of the Forrester. It's the only reason my wife won't trade her Legacy in on one.

tire pressure to low?how about alignment?

I own an '03 Forester auto and haven't had MPG that low - 14. Mine, in city driving, usually runs 19 at the very lowest and that's with the a/c on, but I don't do a lot of hill driving.

It needs a 4 wheel alignment. Tire pressure is kept about 35 PSI.

 

~Howard

 

 

 

Originally posted by jimpomm

tire pressure to low?how about alignment?

I live in the SF area and my Subie Forester averages 25 MPG.

I rarely get really stuck in traffic to the point where I am stopped and the weather is good here, so no snow to buck.

Some folks who live in the country do much better than I do.

Oxy sensor? Our 02 Forester had a myriad of problems, which all cleared up when we had the oxy sensor replaced. It did NOT set off a CEL. We were lucky enough to have a mechanic who knew that our Foresters have problems with oxy sensors.

I had the front oxy sensor replaced once by the dealer under a recall.

Let me add that this Forester is an AUTOMATIC.

 

~Howard

 

Originally posted by Lesbaru

Oxy sensor? Our 02 Forester had a myriad of problems, which all cleared up when we had the oxy sensor replaced. It did NOT set off a CEL. We were lucky enough to have a mechanic who knew that our Foresters have problems with oxy sensors.

my 2k forester (traded in dec.) always got about 22-24 in town and about 26-29 on the highway and it was an automatic. It had about 75k on it when we got rid of it...maybe it was more seasoned (broke in engine)?

 

Try the O2 sensor though...my impreza is a little funky and that is the first thing I am going after as soon as I can...

 

Matt

Subeman90:

Replace the 02 sensor even if i'm not getting a CEL ?

Like I said I'm going for a tuneup first.

I forgot to mention I'm using the oxygeniated winter fuel plus I'm using Auto RX (in the cleaning phase) to see if there any junk in the engine.

 

~Howard

 

 

Originally posted by subeman90

my 2k forester (traded in dec.) always got about 22-24 in town and about 26-29 on the highway and it was an automatic. It had about 75k on it when we got rid of it...maybe it was more seasoned (broke in engine)?

 

Try the O2 sensor though...my impreza is a little funky and that is the first thing I am going after as soon as I can...

 

Matt

After I got a B&M Transmission service at my dealer a few weeks ago, my MPG went back up in my Impreza. Maybe look into that when you go in for the tune-up.

 

By the way, the PCV valve is very oh so easy to do yourself...save a few $$$$$

 

Kevin

Originally posted by howards11

Replace the 02 sensor even if i'm not getting a CEL ?

Yes.

99obw:

Just let me make sure I understand. Replace BOTH sensors (the after catayst and the before catayst) ? I am thinking of buying Bosch brand for both.

 

~Howard

 

 

Originally posted by 99obw

Yes.

Only the one before the cat. The other one just verifies the cat is working.

I get 9.31litres/100km or 22.25mpg with my '00 5spd forester and I drive the car hard with no thoughts about fuel economy and this 22.25 mpg is during winter.

 

This went up 10% since I was hacking around with the air intake and noticed that there is a banana shaped chamber right before the 90 degree bend to main airbox. It points down. It's pretty delicate and someone (mechanic?) had broke it off. They rammed it in all the way which blocked about 2/3's of the airflow. I pulled it back out and clamped it. Drives smoother and accelerates quicker.

 

That alone made a 10% improvement on my mileage. I'd also go with a new o2 sensor, might seem like alot (~$50 here), but i've been driving for 100,000km and wasted 10,000 of that due to air restriction, 10,000/500km per tank = 20 tanks of gas x $35cdn/tank = $700. Well worth the cost.

 

BTW: did you check to see if any of your brakes are seized? My back left was stuck and it caused me to go down to 350km/tank, very hot rim, stinky smell, warped disc, new pad... you get the picture.

99OBW:

Is this the one called the FRONT O2

sensor ?

 

~Howard

 

 

 

Originally posted by 99obw

Only the one before the cat. The other one just verifies the cat is working.

Yes. You can replace it with an OEM part, or buy an aftermarket replacement for slightly less, or buy a universal replacement for even less and splice the wires.

990bw:

Thanks for your help. I'm going to call my mechanic on Monday and setup an appointment.

 

~Howard

One final question:

I was rear ended the day after Thanksgiving. The woman wiped out my exhaust system (tailpipe, muffler and trim piece). Her car slid under mine !

Could have this accident caused ONE or BOTH sensors to malfunction without having a CEL appear ?

 

~Howard

I would have concern about kinks or cracks in the exhaust system.....If the ins. company is paying demand a new exhaust system front to rear (100% complete) and don't forget the O2 sensors too!

 

Matt

that you should have supplied up front. I am sure you did not think of it till now but did your fuel mileage drop after the accident or was it always poor?

I'm sorry for this guys. Lights went off when I realized where these sensors are located. NO....it's too late to demand anything. Happened Friday after Thanksgiving 2003.

I have to pay for this myself. Insurance company paid for tailpipe, muffler and trim piece plus the body work, etc. My body shop guy said I needed a 4 wheel alignment but other driver's company wouldn't pay for that. "Wasn't bad enough."

I didn't start measuring my MPG until recently. Don't remember if it dropped since the accident.

I got an idea that the sensors alone are around maybe $80 each.

How much do you think to install ?

~Howard

installing O2 sensors is a lot like putting in sparkplugs except that you can't use a socket wrench (due to the wire) so it really isn't a big deal to do.

 

1. unhook the wire for the old one

2. unscrew it (sounds easy but can be in a stupid place or really tight)

3. take new one and put anti-sieze on threads

4. screw in new one

5. plug wire in to connector.

6.maybe reset computer (unhook neg. bat cable and let for an hour) Might be better to start with this step anyhow.

 

slightly off topic: i did this to the mercury in my sig. and it took me 15 min.

 

helpful tip: do this when the engine is dead cold

 

hope this helps....

 

Matt

Make sure you have a wrench that fits exactly.

Back in PA you have salt so it may be more of a struggle.

Use a 22mm wrench. I have to disagree on the cold engine, running the engine to get the exhaust hot before you try to remove it expands the exhuast and makes the sensor easier to remove. Be careful with the hot exhaust.

 

Correction:

 

4. screw in NEW one