MPG Question

[M1C8A3L]

Hey guys,

I am a new member to 318ti.org so I apologize ahead of time if this thread is posted incorrectly. I have owned my 1997 for about three months now and it has 98k miles. I love everything about it except that i have been getting a consistent 18 MPG. I drive 80/20 town to highway but I still would expect to get better numbers. My mechanic said that the lowered MPG is due to the cold weather. Do you guys know whether or not the weather could sway my MPG so far off of the average?

I use premium fuel.

Thanks for your help,

-Mike

[Recon427]

Hi Mike,

A similar question to yours is being followed in my thread: http://www.318ti.org/forum/showthread.php?t=29207

Anyways, just as a recap check these things:
1) Spark Plugs
2) Air Filter
3) Fuel Filter
4) Proper Tire Pressure
5) Excess weight in car

Also note that you are using a heavier weight oil [5W-30] and the gasoline that is put out there now is winter gasoline. Meaning it has butane and other additives that help your car burn it easier and thus consume more.

[M1C8A3L]

Thanks for the reply.

I will look into replacing those things.

I have seen many say that a replaced o2 sensor can also significantly impact MPG, do you think that would be better than any of the other options?

[Recon427]

Well, replacing your O2 sensor is the most costly endeavor, relatively speaking. I think they start at around $60 at Advanced Auto Parts. However, if the O2 sensor was faulty it would throw a Check Engine Light. Where as a fuel filter or spark plugs won't necessarily do that.

Your car has 98k miles. The O2 sensor should be replaced every 100,000 miles. This is covered by Inspection II at your BMW shop...so, if you do most of the work yourself then go ahead and replace it.

[vjmvjmvjm]

Originally Posted by M1C8A3L

I am a new member to 318ti.org so I apologize ahead of time if this thread is posted incorrectly. I have owned my 1997 for about three months now and it has 98k miles. I love everything about it except that i have been getting a consistent 18 MPG. I drive 80/20 town to highway but I still would expect to get better numbers. My mechanic said that the lowered MPG is due to the cold weather.

That seems very low, even for winter conditions. I've never gotten below 24 mpg on a tank. As others have suggested, I'd start with the usual tune-up / Inspection I/II items.

Vic