[oldnail]

Hi folks,

Recently changed my 54 plate E90 320i petrol SE for an LCI 318i petrol SE with Efficient Dynamics.

Given the significant drop in CO2 output (175 versus 142) and the significant decrease in combined fuel consumption (around 38 versus around 48), I was expecting an improvement in my fuel consumption.

However, I'm finding that the new model averages around about 34 mpg which is just about the same as my previous model. Given how the official fuel economy figures are calculated, I wasn't expecting anything close to them, but I would have thought that 40mpg would have been within easy reach.

My daily trip to work consists of a 20 mile round trip, with 8 miles of reasonably uncongested motorway, about 4 miles of city driving, followed by 8 miles of country road back home again.

I've been back to the dealer with the car and it has had a software upgrade which hasn't really improved things. The dealer reckoned that 34 mpg was pretty good from a 318i.

Is anyone managing to get into the 40's from this engine?

At the minute, I am quite disappointed with the car (I find the electric power steering a bit noisy and vague compared with the previous car, was told that they're all like that and there's a strange whine/tone from somwhere in the drivetrain, again, told that they're all like that).

Given that a 318d or 320d is well outside my budget, I'm starting to feel the urge to replace it with something with a VW diesel under the bonnet!

[MEGA]

Why is a 320d out of budget? They are similar price used for an 07 320d as an 07 318i isnt it?

I only get 29 from my 320d though I think the problems lay with your right foot dude. Nothing more!

[the_rangdo]

I've got the same engine, albeit a 320i auto.

My commute is 50 miles round trip, 50:50 m-way and 30/40mph roads, getting 37-ish as per the OBC (last time I calculated it properly the OBC was only out by 1mpg so I only occasionally do a comparison for 'calibration')

On a decent mway run I was getting in the mid-high 40s.

[swanseahammer]

My 320d (177bhp - ED) has averaged 39mpg over the last 8000 miles (since I've had the car). 80% town driving, 20% 100 mile motorway trips. More than pleased with this since my previous car, Honda CR-V 2.0 petrol, would get no more than 25mpg with the same driving. If anything I probably drive more "enthusiastically" with the 320d.

[JLR1969]

320D ED Re-mapped to 215BHP averaging 50.6mpg since new, done 11,300 miles. 70% motorways

[oldnail]

Thanks for the replies so far folks, it gives me something to compare against and some food for thought.

I was expecting some sort of economy improvement with the ED but it has failed to materialise unfortunately. It may be down to my heavy right foot but, even driving like a granny, the car sits around 34 mpg. It's very interesting that the auto will give better economy.

There definitely (as expected) looks to be a significant economy improvement with the diesel. This part of the world, even second hand, there's usually some sort of premium for a 320d over a 318i ... I'll just have to look at breaking open the piggy bank!

[MEGA]

Originally Posted by JLR1969

320D ED Re-mapped to 215BHP averaging 50.6mpg since new, done 11,300 miles. 70% motorways

Hmmmm. Please don't take this the wrong way, but... Unlikely. Calculate it, rather than relying on the OBC. Usually post remap the OBC fuel economy figures are up the chuff, although I think a *Real* remap gives far more accurate reading. A tuning box will totally screw with the OBC mpg readout...

[TMP]

Originally Posted by oldnail

Thanks for the replies so far folks, it gives me something to compare against and some food for thought.

I was expecting some sort of economy improvement with the ED but it has failed to materialise unfortunately. It may be down to my heavy right foot but, even driving like a granny, the car sits around 34 mpg. It's very interesting that the auto will give better economy.

There definitely (as expected) looks to be a significant economy improvement with the diesel. This part of the world, even second hand, there's usually some sort of premium for a 320d over a 318i ... I'll just have to look at breaking open the piggy bank!

Maybe it is your right foot - How harder are you having to drive the 318i so it goes like your 320i? To attain those 318i combined figures I imagine you would have to drive it very sloooow.

Originally Posted by MEGA

Hmmmm. Please don't take this the wrong way, but... Unlikely. Calculate it, rather than relying on the OBC. Usually post remap the OBC fuel economy figures are up the chuff, although I think a *Real* remap gives far more accurate reading. A tuning box will totally screw with the OBC mpg readout...

My remap only altered the comp by 1mpg (more accurate) so I can totally trust my OBC.

[the_rangdo]

Originally Posted by TMP

Maybe it is your right foot - How harder are you having to drive the 318i so it goes like your 320i? To attain those 318i combined figures I imagine you would have to drive it very sloooow.

I think some of the engines are getting a bit mixed up in your post there

However, for the record I don't drive it slow. I also don't drive it overly fast/spirited on my commute, the conditions don't allow it.

M60 ringroad in rushhour I prefer to go a steady 70-ish and keep out of the ejeets ways, I CBA with the kangarooing of accelerator/brake to get to work a few seconds quicker.

Getting onto the M67 though, it's not that long and fairly empty so I do tend to push it a little

[poggy]

I get around 36-38 combined with a non-ED 318i. Do you have bigger wheels, that may make a difference?

[Neil McRae]

get shot of rfts will save you upto 2mpg if you do alot of town driving!

[dziqsek]

My MPG is :

town ( speed max 40mph) - 39-42mpg

Highways and normal roads ( speed 50-120 mph ) - MINIMUM () 34 -52mpg max

[Carrera RSR]

Oldnail, to be honest a 10 mile one way, 20 mile round trip a day isn't going to return you max mpg figures no matter how you drive. The journey is far too short and the engine has hardly warmed itself up. I guess you have also only had the car a month or so. So you are still running in at this average mileage. It's far too early and far too few miles to get an accurate reading. It took me a month and 4,000 miles to start getting 40+ mpg from my 320d. A further month or two and 10,000 miles before it has now settled at 44mpg (lots of motorway and a heavy foot).

Also bear in mind you will probably be pushing your right foot down harder in a 318i versus a 320i to maintain similar speeds. Although in manufacturer tests the 318 may be more the more frugal engine, in the real world the 320 may be the better engine in terms of mpg, bhp, mph balance.

For the record I have just done 2500 miles across Europe with a fully laden car with roof box and bike atop the car. Achieved an average of 55 mph with a 39.7 mpg. Happy with that. Average 550 miles per tank.

[JLR1969]

Originally Posted by MEGA

Hmmmm. Please don't take this the wrong way, but... Unlikely. Calculate it, rather than relying on the OBC. Usually post remap the OBC fuel economy figures are up the chuff, although I think a *Real* remap gives far more accurate reading. A tuning box will totally screw with the OBC mpg readout...

I have an Evolve re-map which I hope is 'real' enough.

I have checked using the OBD and the old fashioned way and my car 100% averages well over 50 mpg.

Perhaps as you are a young un your right foot is a little heavier than mine

[Carrera RSR]

Originally Posted by JLR1969

I have an Evolve re-map which I hope is 'real' enough.

I have checked using the OBD and the old fashioned way and my car 100% averages well over 50 mpg.

Perhaps as you are a young un your right foot is a little heavier than mine

I reckon if I drove at 60mph on most of my long journeys then 50mpg would be easily achieved

[Geoffo]

Fuel consumption is around the 42.5 mpg & thats on a 2006 318d @ +/- 70 mph.
50/50 split with motorway & city.

[gerbil_b]

My 318i at the moment is averaging 36.2mpg. I have had it up at 50mpg on motorway driving but as soon as you turn off the motorway it plummets, i live in lewis so all raoads are "B" class, no duel carriageways so average is around 32 - 38mpg, never thought it to be a problem. If i wanted 40 odd i would have bouht a diesel.

[oldnail]

Thanks for all the useful info on this thread. Since I posted last there has been a steady improvement in the fuel economy and the last couple of tanks have been averaging around 37mpg, still short of my target 40mpg but starting to get there.

That was until about one week ago whenever the engine started misfiring periodically. This gradually worsened and I left the car in with the dealer today to get looked at.

It turns out that there was a problem with the spark plug and injector on cylinder 3. These have both been replaced, so we'll see if this improves things further. Hopefully, this isn't the start of some of the woes that other forum members have had with the 2.0l petrol engine!

[JLR1969]

Good luck mate, I always assume that a new car will be problem free as it should be.

[oldnail]

Originally Posted by JLR1969

Good luck mate, I always assume that a new car will be problem free as it should be.

Thanks!

This is my third BMW, the previous two were used ones, this is the first brand new one that I've bought. Ironically, I never had any significant problems with the previous two (a failed parking sensor after 3 years on the first one and a failed bonnet closed sensor after 2 years on the second one are the only problems that I experienced).

Like you say, the assumption would be that a brand new car should be problem free!

[lunar524]

My car is a March 2007 E90 318i 2ltr auto, and the computer is showing a average of 39.4 mpg which I think is quite good for a automatic, on a long motorway run it usually creeps up to about 40.8/9 mpg.

[oldnail]

Another update. Since I've had the spark plug and injector replaced, the car has been running (almost) perfectly (I've had one misfire in the last month). It also feels like it has a bit more power.

The downside is that the mpg has taken a dive again and is back hovering around 34 mpg (no different from my previous 320i). So overall, I'm still not overly impressed with the whole efficient dynamics thing.

BTW, has anyone noticed that the CO2 output of the 318i SE has been revised upwards on the BMW website? The CO2 output of the 318i SE is now listed as 146g/km (my registration book lists 142g/km).