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1984 190e 2.3L euro 1983 300DT
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114 Posts
Discussion Starter #1
I have a question on how Betsy's alx air valve works. Here in Utah it was warm and she started ok not great but ok then it went back to winter and she threw a fit the only way she would start is if I opened the air cleaner and O so slightly put just a little press on the mas air plate for about 45 sec then she idles and warms up but now it is warm again and she starts ok again. My question is the operation I have electrical and coolant going through valve. When you come out in the morning (over night temp 45) should the plate be closed or should the plate show passage. My thinking is when cold it should be shut to give less air to the more gas but I have talked to 15 different techs it s about split down the center I don't think they have any idea just like me. Then as it warms up it shows more passage to lean out out that is my idea. When I go out in the morning she is showing passage and when I get home it may show just a hair more passage not not a hole hell of a lot. I was waiting for the 3 disc set that I ordered to check it out but it has not arrived yet. Betsy is a 1984 190e 2.3L 8 valve manual tranny. I have tryed to attach pics of the valve.


alx air valve 001.jpg

alx air valve 002.jpg
 

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W245 Moderator
2009 C300 4MATIC
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3,302 Posts
I have the auxiliary air valve too (and yes, as it heats up by the heated element inside, the plate it's normally closing)... Here are some general testing procedures for it:



 

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Registered
1984 190e 2.3L euro 1983 300DT
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114 Posts
Discussion Starter #4
Ok samoila stefan I checked my valve as per your diag sheet O by the way thanks. Here in Utah it is 70 degrees right now I removed both vac lines and looked into the valve I cannot see through it so I started up to see if it would move once the car was warmed up it didn't move at all so it looks like my alx air valve is junk any other ideas??? thanks
 

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W245 Moderator
2009 C300 4MATIC
Joined
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3,302 Posts
Could be just stuck (inside there is a metal disc that is pushed to close by a bimetal spring - with an electrical heating element also).
 

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W245 Moderator
2009 C300 4MATIC
Joined
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3,302 Posts
Quoted from a website:

The Auxiliary Air Valve

This item is a device to aid the engine when cold by opening a small port to increase the engine's idle speed. The fast idle control is achieved by the port being held open by a bi-metalic strip that when heated by it's own heater element, or via natural heat soak from the engine, the port closes. The voltage supply to the air valve is the same as the feed to the fuel pump and the warm-up-regulator. If it is found that the idle speed will not reduce and that the speed is maintained artificially high when warm, clamp the rubber pipe between the air valve and the inlet manifold. If this action causes the engine rev's to return to normal, the fault is within a sticking auxiliary air valve.
It is worth cleaning the valve, lubricating it and re-test it's operation. The internal heater element can also be checked for continuity using a multimeter.



Figure 6.8 shows an auxiliary air valve diagram and figure 6.9 an auxiliary air valve photograph.


So, strd27, your new alx air valve is showing passage now with engine cold? I'm going to investigate mine today...:)
 

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1984 190e 2.3L euro 1983 300DT
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114 Posts
Discussion Starter #7
Yes my new valve shows passage my old one showed very little passage but it did show some the new one shows a lot more passage and what a difference on start up and warm up time Betsy acts totally different.
 
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