Loud sound in 1st

[isaacekblad1]

I bought a 325i 2003 a few weeks back. For the most part, it drives great. I've noticed that when I first start up the car and drive in 1st, the engine sounds especially loud. Not loud in a "there is something seriously wrong here" kind of way. It just sounds airy and it feels like it's lacking a bit of power. I wish I could be more specific. My girlfriend says it sounds like a larger truck. Once I open it up on the road after I'm out of my drive way the sound goes away. I don't have this in the higher gears. I'm getting lean codes and will be fixing some small leaks on the intake bellows. Could that be the cause of this noise?

[MIKYZZ4]

Open the hood and check Secondary Air Pump,
should operate for about 90sec. upon engine startup.

[MarcoZandrini]

Th first step in diagnosing a problem is to scan the engine computer (DME) for codes.?5)3 Service Engine Soon light is on only when an emissions related code is present.

[isaacekblad1]

Open the hood and check Secondary Air Pump,
should operate for about 90sec. upon engine startup.

It seems to be longer than 90sec. I also notice that my gas mileage will oftentimes be under 10 MPG when I'm in first. The check engine light isn't on.

[MIKYZZ4]

Wait a minute,
did you start this thread over your mileage gauge?

Perform an intake smoke test,
then post back with results!

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GET RID OF THE LEAN CODES!