20% gas mileage drop in my 2000 328i

[stuhuff]

All, just wondering if I could get any help or tips on why my gas MPG has dropped almost 20% over the last 2 months. My check engine light has not come on, I have performed all maintainance up until now - car has 55K miles on it. The only clue I have is that when I first start the car in the mornings it makes a "whoofing" sound every 2-3 seconds as it is idling. Once I make it to the end of my driveway and head out the whoofing is gone. I used to get 20-21 MPG like clockwork but now am getting 16-17 MPG.

Any ideas?

Thanks

 

[MrElussive]

Are you changing your oil at the correct periods? Have your driving habbits changed at all, lately? Maybe you have been heavier on the accelerator than you used to be....

 

[stuhuff]

All maintainance has been performed. My driving habits are the same.

Guess I will have to go to the dealer and shell out some bucks for them to tell me what's going on...

 

[george]

this is what i think might be going on.......
make sure you use 91 octane!!! anything less will result in poor mpg and loss of pwer!!.
make sure your tires are at the right PSI's.
clean out your injectors.(add some a octane booster)
or i guess get it checked out....