Problems w/ 2003 Bmw 325i

[Bmw 325i 7803]

Whenever I start the climate control either with the snowflake button pressed or without there is a strange smell, but after a while with the ac on it goes away..... I also get the smell when leaving the moon roof open and driving on a warm day, it's almost as if it comes from the engine. ( its not a pleasant smell)

Also sometimes roughly every other day, but usually with the ac on.... the engine seems to take in too much air, not to sound ignorant but it sounds like a vaccum cleaner, and the higher you rev the engine the more of the "blowing" sound you get, it usually cuts out after a while and the throaty engine growl comes back to normal, but it keeps reocurring.

And I also noticed (wallet felt) it only gets 11 mpg in the city, but it does get 27 on the highway. And the on board computer after a 500 mile in a day trip to Pennsylvania says i got 17.9 mpg. As if it averages all the fuel comsuption since purchased. Since i know i didnt get such poor fuel economy on the highway otherwise I would have had to retank before 381 miles (still had 2.7gallons left), and i know it doesnt fare that well in the city since the best mileage I have ever got was 186 on 14 gallons.

What should I do? (sorry for the long post)

 

[Bmw 325i 7803]

Also the car is less than 4 months old and has only 2900 miles on it, and about a good 1700 are highway miles, its always gotten poor fuel economy in the city but i figured it was just the break in period and let it slide.

 

[NZL]

I have a 2003 3series too, about 9,000 miles on it. I noticed when I turn the aircon OFF I get a sweaty smell coming through the car. I don't recall having this problem with any other car I've owned.

Anyone else get this?

 

[jrt67ss350]

It's just the condensing moisture in the A/C system that creates the sweaty smell upon turning the A/C off or when initially turning it on. My E30 does it, my Camaro's Vintage Air A/C system does it, and my parents' 2002 Impala does it, and my dad's '89 S10 pickup does it.

The loud "vacuum cleaner" sound that you get intermittently, especially with the A/C on is the belt driven fan - when the airflow over the radiator becomes hot, the fan clutch locks up, coupling the fan tightly to the water pump pulley. When you rev the engine, it gets louder because the engine spins the fan faster. When the airflow over the fan cools down a bit, the clutch uncouples, the belt driven fan slows down, and you get your "throaty engine growl back." Sounds perfectly normal to me. I drove a 2000 323i this past summer for work, and the noise surprised me the first time I heard it - that fan really can move a ton of air!

 

[Bmw 325i 7803]

That seems to make sense, but what about the 11mpg fuel economy in the city??

 

[Krafty04]

One way to avoid the "smelly smell" is to turn off the A/C and let the compressor wind down for about a minute before shutting the engine off. It also helps the oil drain down to the bearings in the compressor before just "killing the motor".. Also will help with the clutches in the compressor trying to engage while you turn the engine over (if you leave the button pressed in). my .02 cents

jrt is dead on the money explaining the loud sound.

krafty

 

[MrElussive]

I doubt you're getting 11mpg in the city unless you are accelerating very hard all the time. When starting from a stop light in the city, don't gas it too hard, that is when your fuel economy is the worst. It takes a lot of power from the engine to get the car moving, but once you are in 3rd gear and moving along, your fuel economy will be okay. Also, maybe give the car another 1,000 miles or so to fully break-in...usually new cars take almost 4,000 miles to get the proper fuel economy.

 

[Tweet227]

I had the sweaty smell in my'98 328 whenever the A/C was off but the air was blowing. In the '04 i have a milder smell in the same situation. I have just gotten used to it

 

[SFCA-325i]

[snipped]

the on board computer after a 500 mile in a day trip to Pennsylvania says i got 17.9 mpg. As if it averages all the fuel comsuption since purchased. Since i know i didnt get such poor fuel economy on the highway otherwise I would have had to retank before 381 miles (still had 2.7gallons left), and i know it doesnt fare that well in the city since the best mileage I have ever got was 186 on 14 gallons.

What should I do?

What you need to do is reset the MPG computer. When you have the MPG on display, hold in the turn signal stalk (by depressing the BC button for a few seconds) and the MPG will reset (the numbers will vanish and - - - - will appear).

You reset the average MPH the same way.

Both figures are averages since the last time the MPG / MPH was reset.

 

[bmwrocks]

I have gotten the advertised fuel economy in mine since about 100 miles. That's 19 city and 26 highway. I actually get 27+ on the highway cruising 70-100.