Sounds perfect to me.  My manuals don't include anything about AC, so I can't give help "by the book".  But it sounds perfect if AC doesn't affect idle speed.

-Dave G.

DesertStar - 2/2/2008 11:56 PM I spent the day installing my electric vac switch for the A/C such that when activated idle rpm is suppose to increase. This should be the conclusion of my idle troubleshooting and getting everything back to "normal" as far as electrical and vacuum connections. My question: When my G is at idle of 800-850, I activate A/C and I can hear compressor start, but cant hear or see a significant increase in idle rpm. However, the rpm remains around 800 with A/C on. Before I hooked up the electric vac switch/valve my idle would drop to 700 or so when A/C activated. Is the increase in idle when A/C is on suppose to be "an actual increase" to 1000 or so or is it just suppose to increase enough to keep at "normal" idle of 800-850 ? I probably shouldn't worry as long as my G is still running with A/C on, but I am a bit anal about things "being rite" (right ) Mike

Mike:

Do you have further details about your electric vac install? I have the same issue with my 280 GE when the air is switched on. I did nothing to compensate when I installed the AC last year ... My idle is at about 700 RPM w/o the AC on and drops obviously when it switches on. Was the install difficult? Lots to adjust? Anything you can tell me would help loads as the AC is already in use down here in Houston ... 

Hi Drew, I had to take an hour an retrain myself on this subject matter. Here is a thread worth reading to familliarize yourself with some of the working of the sysytems within the same components.

http://pointedthree.com/disc/forums/showthread.php?tid=9927&posts=9&mid=102013&highlight=ventil&highlightmode=1&action=search#M102013

Here is a photo of what I did, it took about 30 minutes, as I like to neatly run my vac lines and electrical. Give me another holler if I am unclear here.

Disregard other info on top of photo as that was when Bram_R and I were troubleshooting other issues in the idle system.

Mike

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Drew, I forgot to mention there really is nothing to adjust and the switch new is around 50.00....or you can get one at a junkyard for 2.00.  They are quite common on most 80's models and are found commonly on the firewall.  I mounted mine on driver side inner fender.

Roly, you are probably right, I never really measured that close.

Mike 

Mike:

Thx for the pic and the explanation ... Mine has never been touched by Fedralizers and so I guess the deal is just splice in the cross T and wire up the electric to the compressor leads ... I gather one wire is for + and one for - ...

Thx for the # Roly ... 

Correct...that is what I did.

Mike

Hey Mike

If you sent me a larger version of the image - I can't find it ... I have my little module ready to go in, but I don't know that I can see where to splice ... Could you repost it larger, or send it direct to me? Also, did you use a little wiring module to plug the power into the  vacuum module or just to connectors?

Here is the image. I had a female plug lying around so I just wired that to plug into vac switch. Whenever I visit junkyard I am always cutting some good connectors and wiring from the dead cars for use later as the need arises.

Mike

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I just cut the existing vac line and spliced in with the rubber connector.

Vac line:

http://www.autohausaz.com/search/product.aspx?sid=vjpik02rilfdtu45fi423hik&makeid=800016@Mercedes&modelid=1193273@280E&year=1981&cid=18@Electrical%20%26%20Vacuum&gid=5024@Vacuum%20Hose/Line

 Also note, I just put a rubber plug on the port facing downward (direction of electrical connection)

Mike 

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I cant tell you what color as I do not know. You will have to look at diagram and see the line that runs between the two other lines. Here is a photo. Look at the red/yellow arrow and red circle. Now go get your hands dirty.

It will be obvious...it is a vac line that runs between two bigger "air slides"....which when "energized" with vacuum, allows that much more air to increase idle.  Pretty cool. 

Mike

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decel1a [800x600].jpg (97KB - 8 downloads)

Just morbid curiosity here, Mike.  I don't understand your drawing.  Are there two lines spliced into the existing line and both of those going back to the valve?  What does the valve do in that case?

My only input is that if you're letting more air into the system, make sure it's filtered air.  Letting a valve just bypass the throttle plate is best.  Better than a valve to provide a separate path into the system downstream of the throttle plate.

-Dave G.