Average MPG??

Hi everyone,

My MPG has been lurking around 18.8 and used to be at least 20! What could be causing this? Checked my tire pressure and have some idle issues which should be fixed once I clean my ICV? Any idea how I can get it Back up to i guess normal which should be around 25mpg? Thanks

O2 sensors and VANOS come to mind. What's your current mileage?

So done the vanos and not getting a check enginee light for o2's!! Got 113k miles 2003 e46 coupe

113k miles, do you have any leaks/holes in your intake boots?

Is this freeway mileage or around town?

The boots Was replaced 2 yrs. Ago and in its both highway and city miles

118k miles. 30 hwy. 21 city. About 24 mixed city/hwy.

Change your air filter if your mileage goes down. Or clean/oil your K&N if you have that.

.02

I was getting 22 hwy/city mile, and that was before I found the oil leak and changed out the oe spark plugs and Valve cover (oil on the plugs). I also cleaned the ICV and TB. Hope mine goes up, we'll find out this week.

When you clean your ICV take the time to clean your Throttle body also. After your ICV is out, its only four bolts, and an electronic clip. The front of mine was not bad, but the back side was covered in grime to the point it was restricting movement. There is a orange rubber gasket on the back, make sure that is in good shape also.

Clean TB, DISA, and MAF sensor.

Replace air filter and spark plugs for starters.

I was getting 32 highway in my 325 but it was fully maintained.

32 mpg! nice, now I have something to shoot for. Before fixing stuff on our new car I was worried b/c the Bimmer got less mpg than my Camaro.

119k 323ci 5 speed. 28 town / 34-35 highway. Maintenance is up to date and just replaced my fuel filter which gave me an extra 1.5 all around.

These are my average numbers to be honest, even with some spirited driving and high shifts.

Well.. Depends on whether we're talking about the OBC display or calculated based on miles and fuel fills.. The OBC usually over-predicts by 2-3 mpg.. Calculated, I used to get around 21-22 mpg city, 30-31 mpg hwy and around 23-24 mixed... A little more in the summer, a little less in the winter. '04 325i with 5-speed manual and around 80k..

My digital read outs don't actually work correctly. All I can see is mileage, time, and trip. I can't reset or anything, so I use the old method of, fill to the first click, drive, fill to first click, divide mileage by gallons.

/Sorry about thread jack?

It's very difficult to located where I might be experiencing this as i've done numerous things and has not improved it! My next move is cleaning the ICV and see where that takes me I guess but my ride drives like a tank (slow and heavy)

Originally Posted by Jagean

My digital read outs don't actually work correctly. All I can see is mileage, time, and trip. I can't reset or anything, so I use the old method of, fill to the first click, drive, fill to first click, divide mileage by gallons.

/Sorry about thread jack?

Agreed, that's about as accurate as it gets.. And when you average that out for several tankfuls in a row, you get a good measure of the true mpg...

Originally Posted by sammk

Agreed, that's about as accurate as it gets.. And when you average that out for several tankfuls in a row, you get a good measure of the true mpg...

Using this same method I clock 23mpg city 25 regular hwy. I took the tollway out of Austin back to San Antonio cruised about 90ish and clocked 26mpg.

Originally Posted by edz2003

It's very difficult to located where I might be experiencing this as i've done numerous things and has not improved it! My next move is cleaning the ICV and see where that takes me I guess but my ride drives like a tank (slow and heavy)

Driving like a tank is not good, imo (for as little as it counts) it seems like your not getting enough of something: spark, gas, air (those are the easy ones to check). Make a check list, and take your time, also, check your codes anyways. My light doesn't come on, but it will still store codes. I just figured my light is burnt out.

also Edz, how long has this been going on?

Originally Posted by edz2003

not getting a check enginee light for o2's!! Got 113k miles 2003 e46 coupe

Replace them anyway. They're worn out.

<<<<<<<<<<<<<<<<< comfortably gets 36mpg

Originally Posted by aikmanson

119k 323ci 5 speed. 28 town / 34-35 highway. Maintenance is up to date and just replaced my fuel filter which gave me an extra 1.5 all around.

These are my average numbers to be honest, even with some spirited driving and high shifts.

Dude teach me your ways. I get 16mpg city and 25 ish on highways. Gonna do a big tune up soon do hopefully that helps