balancing the throttle bodies - what to do with (archive)

the idle control valve?
I see vacuum ports at each throttle and the adjusting screw under the plastic caps. I gather that they all need to pull the same vacuum to idle best. But the actual amount of air that passed the throttle screws at idle will change the idle speed. This will confuse the computer/icv and make adjusting difficult.
So what is the process, Engine warm obviously, but do I unplug the idle valve and set to one rpm or is there some other precedure?

My idle is a bit rough, which may be normal, but it is also rough around 2000 rpm and does not pull smoothly until after 2500 rpm. New plugs helped a lot, but not perfect. The old plugs looked perfect. Engine has 65000 miles, compression, leakdown, all ok, only uses 1 litre of oil in 3000 miles.

Most garges are afraid to touch this stuff, I am not, and I have the vacuum gauge. Idealy I would get 6 gauges, for now I have 2.

Follow Ups:

Re: balancing the throttle bodies - what to do wit Matt Evans 13:31 6/07/2002 (4)
- Re: balancing the throttle bodies - what to do wit Todd Kenyon 17:05 6/07/2002 (3)
  - Orig part is Yellow. Replaced OEM part is Blue. rcbmw 20:39 6/07/2002 (2)
    - my dealer sold me yellow ones..... bruce 16:11 6/09/2002 (0)
    - Clean out the needles. ian M635 Uk 11:32 6/09/2002 (0)
Todd Kenyon has the procedure here: JamesM 09:42 6/07/2002 (0)

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