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Old 06-16-2015, 09:16 AM
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Stretch Stretch is offline
...like a shield of steel
 
Join Date: Sep 2009
Location: Somewhere in the Netherlands
Posts: 14,461
Quote:
Originally Posted by Stretch View Post
...I think I need to go back to the FSM and see if there's any more information to be gleaned...
OK - that was a merry dance.

No information about this on www.startekinfo.com that I can find.

So I went and had a look in the German language version of the W123 FSM I've got to see if there was a functional description chapter for CIS in either the M110 or the M102 engine sections.

I found them both - but my German is not up to understanding it all. I did find a chapter number though =>

Chapter 07.3-001 that's the one explaining in nice terms how CIS works!

Back to startek - couldn't find that chapter in either the W201, W124 R/C107 or W126 FSMs

I eventually found it "elsewhere" in a W126 FSM

Here's a snippet describing the air idle control valve - from this information it does indeed seem to be working much like I expect a choke to work





It strikes me to be a fancy electromagnetic choke - there's a basic AC signal (what would you call it DC modulated?) that fluctuates at about 200Hz to energize the magnet - the basic DC amplitude pulls the opening to different positions.

This is in some way related to the temperature sender - I need to read some more but have to bugger off elsewhere in a minute so I haven't got the time to get to the bottom of it just yet!

I think the problem I have is possibly related to a leaky diode(s) on my alternator which might be arsing up the excitation voltage for the air idle control valve...

...perhaps that's also happening for you Bob?
Attached Thumbnails
89 300E, W124, M103 High idle... SOLVED-snippet-w126-fsm-chapter-07.3_001-about-air-idle-control-valve1.jpg   89 300E, W124, M103 High idle... SOLVED-snippet-w126-fsm-chapter-07.3_001-about-air-idle-control-valve2.jpg  
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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!
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