my RPM fluctuates but only when gas pedal is pressed slightly, on idle it is perfectly alright and doesnt move around, but when u press a bit of gas it starts to wiggle around, i realised it ever so slightly on the freeway but when i put it in park to verify and tried to set the rpm needle to about 1000 rpm and held it still, the rpm kept going up and down.

i tried looking for vaccum leaks but ddnt see anything !

Please Help !!!!!!

 

Hello, I noticed you have a 2005 E60, how many K's do you have on the car? I've got an 05' and recently had to do the transmission pan and oil change (roughly around 150,000Km's) BUT I definitely had a fluctuation in revs at idle. Also did VANOS Solenoids (symptoms of this is rough driving and shifting mostly at low range)

First things first, Can you get any codes off the car? this will point you in a direction.

 

It has 170,000kms but shifting is smooth in low and high ranges and no oil leaks from transmission pan at all, there are no codes i triple checked and triple checked again !

 

I have an e60 525i 04. It does the same. So far all I changed was the spark plugs, DISA valve, oil, oil filter and air filter. The car feels a lot smoother but I still have the "Slightly push the pedal and hold it on low rpms to FEEL and see it fluctuating." syndrome. Next I'm going to buy ignition coils. If it still does it then I'm going to get the transmission filter and fluid replaced along with updating all software. (DME and TCU) Hopefully this does it! If I find out it's something stupid like a torque converter I'm going to have to trade it in for a Crown vic and corvette! (common I don't want to replace this car with a vic!)

 

How ever if it is fixed you guys are going to see one hell of a clean ass 525i. I love this engine! I also love it in this car! I know for most the power to weight ratio sucks! To moi it's perfect! I like to be able to not be scared playing with high revs through hairpins. This is my point A to B car, my business car, so it better be all about business! ahahah I just wish they sold the bullet proof ones here like they do in europe

 

What business are you in?

 

Could it be a vaccum leak ? Or dirt in the injections?

 

I would suspect injectors too, but did you do the recommended transmission pan and oil replacement before? Don't trust BMW's longlife guarantee on these oils that's just not true, they'll only take out the oil and reuse it... Mine wasn't leaking but it was overdue for a replacement, drove brilliantly after that: but now I've had 2 times where it hesitated at low range so I'm suspecting injectors as well (spark plugs were done not long ago).

As for vacuum leak, I honestly would't know for sure; a mechanic inspection required maybe? Keep us updated. BTW: these are the injectors I'm looking at (under half price compared to others but I'm still a tad skeptical :/)
http://www.ebay.com.au/itm/191559723926?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

I had this very issue, very light pedal press and cruising at about 60km/h:

I fixed the issue originally but changing the transmission fluid in my auto (545I). Doing this made a huge difference in gear changes and made the fluctuation go away for a while. then It came back.

I started to get a whistle (like a fan belt sound coming from the engine when it was started cold) so I read into it and it was coming from two crankcase vent valves, so I replaced and cleaned both of these, and it made a massive difference! the fluctuation is almost gone completely.

good luck, hope this helps