Does it vibrate at idle after fully warmed up at all? Like at a stop light?

I think I trickle charged it about a month back to make sure the battery was maintained and that didn't seem to have done anything for me. Didn't really notice any difference with the charged battery or not. Will give it a try again though.

CCV tubes appear to be fine and its not like its a vacuum idle issue so I don't think its a vacuum issue. All other vacuum lines and CCV's both were replaced just recently after the stem removal.

No it only happens on the initial cold first time start. When the car is fully warm it starts up just fine. And as stated it didn't do it yesterday. I was thinking about it and a better way to state the idle was like if the rpms went down to low and the car was trying to stay on type of deal. Hopefully that makes sense.

In that case intermediate lifters sounds like a possibility as mentioned before. From what I've read you can bump the idle a little bit with programming... hopefully someone with more experience can chime in.

Something over looked is clean the throttle plate from carbon build up. Take the snorkel off and spray a special throttle body cleaner, sold anywhere, and use your finger to open the plat and clean the carbon.

Excessive carbine will give you a rough idle. I did this to mine when I first got it...throttle plate would stick to gummy carbon.

Really? I figured if those were bad it would be continuous warm or cold? If anyone can chime in that would be great.

I cleaned the throttle body a bit while I was in there working on other things. I didn't go crazy though so Ill try your way.

I have the intermediate levers issue. And it only happens on cold-start. (and i my case only in sub-zero temperatures.)

Since your X is a 2004 (like mine) chances of you having the intermediate lever issue greatly increases, since this only relates to 4.4 N62 engines produced between 06/04 to 02/05.
Se extract from SIB below.


SI B 11 02 05
Engine January 2006
Technical Service
This Service Information bulletin supersedes S.I. B11 02 05 dated May 2005.
designates changes to this revision

SUBJECT
N62 Engine - Rough Idle, Misfire Faults after Cold Start

MODEL
E53 (X5 4.4 i/4.8is); E60, E63/64, E65/66 with N62 from 06/04 up to 02/05 production

SITUATION
Customer may complain of erratic engine idle speed lasting for approximately 20 seconds after a cold
start. Check Engine Soon light may be illuminated and misfire faults for various cylinders (e.g. FC
2742, 2743, 2744, 2745, 2746, 2748, 2749, 274E) may be stored in the DME.

CAUSE
Incorrect tolerances and geometry of Valvetronic intermediate levers are causing uneven cylinder
filling during the transitional cold start period (60 seconds after the engine has been started) when the
Valvetronic system is switching from the initial 6 mm to a minimum 0.3/0.8 mm valve lift.

CORRECTION
On a customer complaint basis, and after performing diagnostic procedure described below, replace
the Valvetronic intermediate levers.


If you are curious enough, you can read a design study about the root cause for the issue here:
http://sfsa.org/tutorials/leverarm/BMWValve.pdf

Surging on cold start
 

I also have a 2006 X5 4.8is and when cold surges a few times almost turning off then after about 1-2 min of surging it's fine. No smoke or codes. I do notice a few oil leaks have developed and an occasional VANOS rattle. I have around 120,000 miles on her. Also I've replaced plugs, air filter, vent diaphragms and coolant crossover pipe. Didn't see any sludge in covers. Also vibrating while idling but may just be bad mounts. Replaced several brittle coolant hoses and reservoir but still slightly using coolant. Read something about cams causing problem. I've scanned her with GT1 and everything seems to be fine. Also read about Cam Position Sensors and VANOS O-rings. Not looking to chase a ghost. I have the valve cover gaskets and valve seals. watching for a used tool on ebay which I see one today. What else should I change while in the valves? Also have ordered the dreaded alternator bracket seal due to oil leaking and blowing back under vehicle. That just started about a week ago when I noticed the smell of oil burning while in a drive thru. Never once have I noticed exhaust smoke but I want to replace the valve seals and correct most, if not all leaks due to oil consumption. I've noticed the oil is always low on the stick before it's even half way due. When I say low I mean just showing on the very tip. Once I received a message regarding low oil level and I just replaced it no more than 3-4 months ago. I've been using Mobil European car formula. I'm the second owner and bought her with 80,000 miles. She runs like a scalded dog when I mash on it. I haven't a clue of what she ran like new for comparison but I know the idle is definitely rougher than new.

Gee's if its not one thing its another with this vehicle! So what have you done to resolve the issue or did you just leave it as is? Like you its only at initial cold startup. Not sub zero here though! Is it even worth fixing and if not what type of issues will this lead to? Also got the tranny kick at cold startups which Im going to try replacing the fluids and see if that cures that issue.

Thanks for the info! :thumbup: