[moderat0r]

     Featured on BIMMERPOST.com

Hello,
Car is BMW 2010 323i N52K ENGINE 175,000 Kilometers

I remember after buying car in 2019 I did 740 km/459miles highway ride in full tank of gas around 55liters/ 14 gallons that is like Mileage of 13.5kmpl OR 32.786 MPG US with all passengers in seat and luggage.

I didn't ride a lot in 2020 and 2021 at all, probably I only rode 5000km in total of two years. Most of the time in car was sitting idle home but I was using it less often as I would normally.

Now I am noticing more and more that Mileage is too low, its showing only 6.5kmpl OR 16.786 MPG in dash in city rides and gas tank going empty with low Miles/kilometers run


I remember it never showed that low even in winter or summer.

I am not sure what happened to car. I have had no engine lights ever since I bought the car other than ABS sensor for rear wheel which was replaced recently but mileage was already lower before abs sensor light.

I got oil, oil filter and air filter changed recently and that didn't help with mileage.


Should I get Ignition coil and spark plugs replaced?

Can premium and regular gas make that much difference in mileage?

There is Oil filter assembly gasket leaking oil a little bit so I have to get it replaced, already ordered part.

I also did a scan with OBD bluetooth tool and did not find any warning or codes.

What do you think could be wrong for that low mileage ?


Thank you

[e90yyc]

Most people here are going to understand MPG better than km/l, and probably won't be willing to do the math to convert it, simple as it may be. I would suggest converting those figures to MPG to get more responses.

Yes, that is quite the change, but without information about when the counters were reset it's impossible to know whether there's really an issue. The fuel economy reading is a continuous average, so the reading you got when you first bought the car would have been entirely dependent on how the PO drove (highway, city, heavy foot, light foot...). If he drove lightly, and drove mostly highway miles, and never reset the counter, then your reading will be weighted heavily toward the miles he drove.

Over the period your car sat largely undriven, it's possible the counter was reset due to lack of power. Are you resetting this? Have you reset it?

The only way to really gauge whether you might have an issue with fuel consumption is to reset the counter and then drive in the city like you normally would. Then reset and drive on the highway. This is far from scientific and assumes car is correctly calculating consumption, but it should give you a rough idea of whether you're in the right ballpark.

The numbers you provide in your post range from about 7.5 l/100km to 15 l/100 km. The latter is certainly high, but not outrageously so if you're in a lot of stop and go, or are idling for long periods of time.

[moderat0r]

Originally Posted by e90yyc

Most people here are going to understand MPG better than km/l, and probably won't be willing to do the math to convert it, simple as it may be. I would suggest converting those figures to MPG to get more responses.

Yes, that is quite the change, but without information about when the counters were reset it's impossible to know whether there's really an issue. The fuel economy reading is a continuous average, so the reading you got when you first bought the car would have been entirely dependent on how the PO drove (highway, city, heavy foot, light foot...). If he drove lightly, and drove mostly highway miles, and never reset the counter, then your reading will be weighted heavily toward the miles he drove.

Over the period your car sat largely undriven, it's possible the counter was reset due to lack of power. Are you resetting this? Have you reset it?

The only way to really gauge whether you might have an issue with fuel consumption is to reset the counter and then drive in the city like you normally would. Then reset and drive on the highway. This is far from scientific and assumes car is correctly calculating consumption, but it should give you a rough idea of whether you're in the right ballpark.

The numbers you provide in your post range from about 7.5 l/100km to 15 l/100 km. The latter is certainly high, but not outrageously so if you're in a lot of stop and go, or are idling for long periods of time.

Edit to Miles and gallons done.

My driving routes in city roads are exact same as it was when I bought the car and I was getting at least 10KMPL or 21 MPG /310 miles in 14.5 gallons in city before until it went down gradually

[e90yyc]

I understand your concern, but unless there’s some measure of consistency it’s really hard to say whether you have a problem.

If you, say, made the same highway (or even long city) trip for the past three years, always reset your mileage average before departing, consistently observed the same fuel consumption when making those trips, but are now suddenly—all else equal—getting considerably worse mileage, then I’d see that as cause for concern.

The issue I’m having is you make no mention of resetting the counter when you bought the car. Unless you did this, you have no way of knowing what the denominator on that average calculation is.

When I bought my car, the previous owner’s average economy was way better than I what I ever achieve. This is because he drove a lot of highway miles and was also a pussy.

Sure, 15 litres/100 kms sounds high for a 323, but not so high that it’s impossible. There was a post not long ago from someone with an N54 who was getting like 6 MPG I think, which immediately would indicate something isn’t right.

Describe your process and when you reset your economy average.

[marvinstockman]

Don't drive yourself crazy, do the following:

1. Fill tank at gas station close to highway entrance.

2. Drive a 50 to 60 mile round trip at say 60 mph.

3. Get off highway and fill tank ASAP.

4. Divide miles driven by gas used, or however you want to calculate it.

Don't top off tank, just let it click stop.

[ctuna]

Terrible in town and good on the Highway (in not hills )
is pretty typical of these cars.
Short drives are the worst.

[sharadn]

If you drive fastidiously on the highway with mileage as your goal you can get around 25mpg. Around town expect to get about 16mpg . This what get with my 2006 325xi e91.

[ctuna]

That's exactly what I get in my Wagon although I used to do around
18 in town but now I am doing ultra short drives in town .
However on long cross country stretches where it was flat and
no traffic disruptions I could get 30 a few time. However the minute
I get back in town it goes right back down.

A 323 in Canada should be 2.5 liter instead of a 3 liter so it should be a little better.