Why my MPG is just 15.4...:(

[tkbr0wn]

Originally Posted by Red Bread

There are all kinds of bikes, segways and shoes that are better suited for this sort of commute. You will continue to get poor mileage with those sorts of trips, and you'll rarely be generating any coolant temp, much less oil temp, which will cause excessive wear compared to an engine that gets to proper operating temp everyday.

This doesn't make any sense to me at all.

Say Person A has a 1 mile commute. He starts up his car and drives to work every morning.

Person B lives right next door to person A and and has a 30 mile commute that leads him right past Person A's office. Are you saying that Person A will have excessive wear on his car compared to person B? Seems to me the first mile they would have the same amount of wear.

[imported_mega]

I would ride a bike or walk 1 mile, it's really hard on a car never warming up like that

[TagMan]

Originally Posted by tkbr0wn

This doesn't make any sense to me at all.

Say Person A has a 1 mile commute. He starts up his car and drives to work every morning.

Person B lives right next door to person A and and has a 30 mile commute that leads him right past Person A's office. Are you saying that Person A will have excessive wear on his car compared to person B? Seems to me the first mile they would have the same amount of wear.

If we finish the assumptions for the sake of discussion, let's suppose that all the wear and tear occurs in that first mile. That would mean that Person B's car will have approx. 1/30th the wear and tear.

What you are forgetting is that the wear and tear is relative to the odometer. In other words, after each Person's odometer reaches 300 miles, for example, Person A's car will have 300 "wear and tear miles", while Person B would have 10 "wear and tear" miles.

I'm not suggesting that I agree or disagree with Red Bread's post, but I do hope this helps make the math more understandable for you.

TM

[tkbr0wn]

Originally Posted by TagMan

If we finish the assumptions for the sake of discussion, let's suppose that all the wear and tear occurs in that first mile. That would mean that Person B's car will have approx. 1/30th the wear and tear.

What you are forgetting is that the wear and tear is relative to the odometer. In other words, after each Person's odometer reaches 300 miles, for example, Person A's car will have 300 "wear and tear miles", while Person B would have 10 "wear and tear" miles.

I'm not suggesting that I agree or disagree with Red Bread's post, but I do hope this helps make the math more understandable for you.

TM

I see what you are saying, but you didnt finish it up.

If Person A has 300 "wear and tear" miles on his car, that means he has made his commute 150 times. Assuming that is the only driving he did then he only has 300 miles on his car.

Person B in the same 150 commutes now has 9000 miles on his car including 300 "wear and tear miles".

Whose car has more "wear and tear"?

I do agree however that Person A should change his oil based on the number of commutes vs. the reading on the odometer. Doest the sensor in the BMW measure the particulates in the oil rather than basing it soley on milegage though?

[driftmotion]

WOW .... for one mile maybe you might want to consider walking ..... great MPG that way and not to bad for your health either .... LOL although you wouldn't have as much fun

[Red Bread]

Originally Posted by tkbr0wn

This doesn't make any sense to me at all.

Say Person A has a 1 mile commute. He starts up his car and drives to work every morning.

Person B lives right next door to person A and and has a 30 mile commute that leads him right past Person A's office. Are you saying that Person A will have excessive wear on his car compared to person B? Seems to me the first mile they would have the same amount of wear.

It's more wear because person a never lets the fluids come to operating temperature. Because the engine never gets a chance to develop those temps, it's shut off before it can, it creates excessive wear. Moisture will never burn off in the exhaust system, combustion deposits don't get burned off and oil never reaches it's proper viscosity, it will be like operating the motor on 5w oil for the life of the car. Short trips are quite hard on motors, you'd be better off taking a round about journey to work to let it warm up.

Since person b eventually gets their car to operating temperature, they aren't suffering from the same circumstances at all. It's a good point that they'll have a smaller percentage of their miles at startup conditions compared to person a, but they'll also have fewer trips where ideal operating conditions are never met.

[TagMan]

Originally Posted by tkbr0wn

I see what you are saying, but you didnt finish it up.

If Person A has 300 "wear and tear" miles on his car, that means he has made his commute 150 times. Assuming that is the only driving he did then he only has 300 miles on his car.

Person B in the same 150 commutes now has 9000 miles on his car including 300 "wear and tear miles".

Whose car has more "wear and tear"?

I do agree however that Person A should have his oil changed much more often.

LOL... OK, you ask who's car has more "wear and tear"? At any point in time, comparing equal odometer readings... which is a typical measurement of vehicle use... Person A's car would be a disaster by comparison. EVERYONE drives that first mile... but most don't stop there. :smile:

TM

[tkbr0wn]

Originally Posted by TagMan

LOL... OK, you ask who's car has more "wear and tear"? At any point in time, comparing equal odometer readings... which is a typical measurement of vehicle use... Person A's car would be a disaster by comparison. EVERYONE drives that first mile... but most don't stop there. :smile:

TM

Thats exactly my point. Everyone drives the first mile so wear and tear is equal. Its all about knowing when the proper time to change the fluids is.

Let take our example out 3 years with the only driving being commutes.

Now Person A has 900 (who knew breaking a car in would take so long) miles on their car of which ALL are wear and tear miles. Lets also assume that he has changed his oil 3 times.

Person B now has 27000 miles on his car with 900 wear and tear miles and lets assume he has only changed his oil twice based on the ~10000 mile intervals and is on his third set of tires....

Whose car is in better mechanical shape? Whose car is going to sell for more?


Obviously, this is overly simplistic and Person A will most likely take the car on spirited runs on the weekend which will do the job of "getting the fluids up to temp" and burning off H2O and such. I just dont buy the short commute is worse than a long commute theory.

[tkbr0wn]

Originally Posted by TagMan

LOL... OK, you ask who's car has more "wear and tear"? At any point in time, comparing equal odometer readings... which is a typical measurement of vehicle use... Person A's car would be a disaster by comparison. EVERYONE drives that first mile... but most don't stop there. :smile:

TM

Also, odometer readings are the typical measurement of vehicle use, but you are missing one key component.... "Time". In this scenario, the cars will NEVER have equal odometer readings because of the very nature that they are being used.

[Red Bread]

It's not just about changing fluids, it goes deeper than that. Carbon buildup will almost certainly be higher, turbos can have more sludge and deposits, the exhaust can wear quicker, the starter will be much more utilized, the battery won't last as long as it's not able to be recharged to capacity, the exhaust gas recirculation system will have run 100% of the life of the car, etc. Changing fluids more often will help, but there's still plenty of excessive wear and tear that simply wouldn't happen in a car driven under normal operating conditions.

[tkbr0wn]

"Carbon buildup will almost certainly be higher"
"turbos can have more sludge and deposits"

OK, will a spirited run on the weekend clean that out?


"the starter will be much more utilized"

Really? How so, seems to me like there are still two starts a day.


"the battery won't last as long as it's not able to be recharged to capacity"

Ummmm, Im not sure that really counts as wear and tear on the car...


"the exhaust gas recirculation system will have run 100% of the life of the car"

The recirculation system will have run exactly the same amount of time Person B's did, or possibly even less...

[Red Bread]

I'm just talking in absolute mileage. You're right, that some things will be the same or similar for the same mileage. Say one car has a forty mile round trip commute, while another has a two mile r/t commute, at 60k miles, one will have had to use the starter about 1500 times, the other will be 30k times. Carbon buildup and sludge would most likely be diminished by a weekend drive, but they'd most likely still occur at a higher rate under these conditions.

[tkbr0wn]

I know we are coming at this from two different angles, but do you realize at 60k miles, the 2 mile commute person would have driven to work. 30,000 times? Thats ~115 years worth of commutes.

IOW, you cant compare these two cars on mileage alone, but mileage vs time.

[Red Bread]

Originally Posted by tkbr0wn

I know we are coming at this from two different angles, but do you realize at 60k miles, the 2 mile commute person would have driven to work. 30,000 times? Thats ~115 years worth of commutes.

Yeah, I suppose this is a bit of armchair quarterbacking. I personally make a point of not driving if it's not going to be far enough to get the oil temp up. It helps that I have a 1000 ft elevation drop over a mile and a half drive from my house down to town, that really gets things warmed up in a hurry, both up and down.

[mywifestolemy1]

....and you're driving to slow.

Originally Posted by sandy198423

My commute to the office is just 1 mile. and I put like 2000 miles till now. Is it because of less commute and more stops that my Mileage is just 15.4? Is it normal?
Please help me guys....

[NJ135]

my average unless i drive like a grandma or go on a highway is about 15-16 =[

[sunnywei2001]

Yes! Could not agree more.
Walk will only take 5 to 10 mins.
It might be a good way to train your right foot.
And have fun during the weekend for +15 MPG in most other driving condition what 135i is design for.

[bman6074]

mmm I am 9 miles to work (all back roads/lights/stop signs). I average 19-22 miles per gallon. I don't baby it but I am not hot heavy to each light. I do coast when and where i can. Especialy if i see a red light ahead i will let the car coast to the light and most of the time when i get there the light is changing to green before i have to stop.

[jeremyc74]

Originally Posted by sunnywei2001

Yes! Could not agree more.
Walk will only take 5 to 10 mins.

If you're walking 5 minute miles you need to be on the next olympic team. :wink:

(Even 10 minutes would be a pretty good pace in work clothes)