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Subject: Changing the idle control valve Author: DavidC (moderator) : member since December, 2003 : 11919 posts Posted on: 2005-09-02 00:48:18

Today I changed the idle control valve (ICV) for a new one on my '86 735i (98k miles) in hopes of resolving the erratic idle problem that often causes the engine to stall or quit when going from Park to Reverse or Reverse to Drive. I've already replaced the rubber boot and every rubber hose I can find on the engine. No apparent vacuum leaks, either, and the oil filler cap is new.

It definitely made the idle smoother and more steady. The engine still quit once, though. It only does it when the A/C is running, making me wonder if the A/C compressor is dragging the engine down, somehow. Still, MUCH, MUCH better than before and the RPM's are fairly steady at stoplights instead of fluctuating like they're going to sputter and stop.

Here are the pics and steps involved.


Use a 6mm socket to loosen the lower hose clamp.


Use a 10mm socket to separate the bracket from the valve cover.


Disconnect the electrical connector.


Pull the idle control valve out of it's hole in the rubber boot.


Remove the rubber collar from the retaining hole in the bracket.

Finally, install the new idle control valve into the bracket, secure the rubber collar, attach the hose and tighten the hose clamp, insert the horizontal end of the ICV into the rubber boot, secure the bracket to the post on the valve cover and reconnect the electrical plug to wrap it up.

David Cecil, KI4GZR
'97 740iL, 130k miles
'92 750iL, 82k miles
'86 735i, 98k miles

www.e38.org has links for everything about your BMW 7-series automobile

• Changing the idle control valve (pic) - DavidC 2005-09-02 00:48:18 (1098 views)
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