Hi All

I have a 525i E60 auto that I bought from new in 2004 it has always been serviced by BMW main dealers in the UK in line with the idrive.

it has now covered 228,000 miles (367,000 kms), while the car still runs like a dream the fuel consumption has fallen from ave 31.2 mpg to 27.7 mpg.

I moved to Southern Spain about 6 months ago (average outside temp around 34 degrees) and so now the air con is now on most of the time but would it make that much difference to fuel economy (in the UK I used run with climate control on most of the time as I had free fuel from my employer (not very green I know!!).


Any ideas what could cause this (I have tried new oil & filter, air filter, spark plugs) or is it just the engine getting old?

Steve

 

Anything could happen at this time. The transmission may not be up to its par at this point. The engine internals may have gunk etc. Try seafoam.

 

If you have climate control, I'd presume it switches on and off according to the temperature demands inside the cockpit.

With the UK average temperature being considerably lower than that of Spains, I'd say the CC easily reached the required temperature in the car and thus switched the AC off accordingly. In Spain it's probably always on, constantly fighting to reduce the temperature of the cockpit, thus increasing fuel consumption.

FYI, AC's are known to increase fuel consumption by upto 30%, so if you say the air con is on most of the time now, this may be the culprit.


P.S. Send us some sun! I'd love to use my AC!

 

I'd be pretty happy just worrying about a small drop in gas mileage at that mileage.

 

that's still pretty phenomenal gas mileage for that many miles. have you reset the mpg setting lately?

 

I think it would be normal on the miles you have on the car,thats a pretty good number IMO

 

Dude... your mpg is phenomenal. I don't know anyone that gets as high as you do on average.

 

Is there a decrease in the grade of gasoline where you are at now as opposed to 6 months ago?

 

Guys, You are quoting mpg in UK gallons I guess so that'll be about 25 originally down to about 22.5mpg US now. Doesnt seem too bad. The drop off could be down to ethanol content in the Spanish gas. I think E10 is allowed there. A little less energy means more volume for the same engine performance. Therefore less MPG. Of course the previous post about AC demand also holds true. The AC compressor clutch will engage only when needed to hold the internal cabin temp. In Spain, the clutch will be engaged longer, and that'll reduce your MPG. I dont think there is anything wrong with your car.