I have a 2005 545i with 50K miles that is doing cold start random misfire, triggering "random misfire" and "increased emissions" code. I have changed/cleaned the pressure regulating valve, MAF, fuel injectors etc. I use Octane 93 Chevron gas. Dealer has replaced intermediate levers and checked everything and still can't find problem. I've been to the dealer 9 times. Did a search here and someone had similar problems and solved it by cleaning the air adjuster valve (DISA). I am familiar with the DISA in the E46 but where is it in the E60? Thanks for your help.

DISA in E46:
http://forum.e46fanatics.com/showthread.php?t=342081

 

On the back of the intake manifold

http://tis.spaghetticoder.org/s/view.pl?1/07/61/60

 

Same place as the E46 since the 2004/2005 E60's had the M54 engine. But you do not have an M54 engine. You can find it just before the intake manifold since it's responsibility is regulating incoming air

 

I had the same symptoms , misfire and cel light came on. Codes read lean mixture.
My Indy guy suggested that it was likely a disa valve failure.
And it was soo.
As he was taking it out the flapper was hanging on. Parts holding the flapper had worn off , plastic of course., he suggested to replace the parts with a kit from german auto solutions.com

I spoke to Garry at auto solutions and he knows the stuff. He said that the oem part has a design flaw, no matter how you drive and the age , or the miles, the butterfly valve and the pin holding it will wear off . His kit is pretty neat .
I ordered it on line for my m54 530 , 2004 . It came in 5 days . Cost is 75 plus shipping.
Had my Indy install and replace the worn out parts with the kit., reinstalled the old disa valve.
Works like a charm.

No rough idle
No misfire
No lean mixture codes
No hesitation at low rpm.
Go check it out.

 

with the hesitation at low speeds did you also feel a kind of vibration?