RPM issues...

[12beat]

Hi all...
I have a funny problem with my 1997 328i. When travelling on the freeway at say 60+mph (2600+RPM) and aproaching traffic or an on ramp I would take the foot off the gas pedal, I notice the rpm's will not drop immediately. It would stay at the same RPM then ever so slowly decrease. At times it will even fluctuate as if I was blipping the throtle. This has never happened before. Has anyone else experienced this issue? Is there a know problem with the 328i?

 

[bmwhighrolla]

my 323is has a slow decel in rpms when i rev it in neutral i dunno why tho i dont really car dont bother me

 

[Kirby]

My 94 325i does that, only slightly noticeable, and always exactly the same. On my car, I'm assuming it is normal. I think this is done by the ECU to prevent stalling on sudden throttle closing. On carb'ed cars they had a small pump called the "Anti Stall Dashpot" that did exactly this.

 

[12beat]

Problem is that it is an auto...

it never used to fluctuate like this before...I'm just wondering if it could be the throtle position sensor. Has anyone ever felt this on their 328's before? I'm getting crummy fuel mileage!!!

 

[epj3]

it never used to fluctuate like this before...I'm just wondering if it could be the throtle position sensor. Has anyone ever felt this on their 328's before? I'm getting crummy fuel mileage!!!

Vacuume leak

 

[12beat]

Where should I look? Is this something I can do myself?

 

[epj3]

Where should I look? Is this something I can do myself?

The intake system, use some carb cleaner or something.