Jetronic on 190e 2.0 auto - what's this adjuster ?

[Greybeard]

I recently took my newly acquired 190e into a local garage with LPG experience to look at a stalling problem on gas.
The petrol running was fine, and idled at about 800. I watched him make a small change to the adjuster(indicated in the photo), which did raise the idle speed slightly.

However, we found there were other issues to be resolved(low coolant/leaking vac pipes) and I left to clear these.

The end result is no change in my gas problem, and so I tried to find out what they had adjusted, before I went back for another look at the original problem.

So far I can find no reference anywhere to this adjuster.
Can anyone enlighten me as to what is and does?
Thanks in advance.
John

 

[television]

Thats a new one on me, Ian walker will know, Ian where are you

 

[star]

Its the throtle venturi stop, not the way to adjust the idle because it'll mess the settings of the throtle venturi switch(which plays up anyway)

ps, nearly got that car, u just beat me to it.

 

[television]

Thank you Star for the info

 

[Greybeard]

Thanks Malcolm, and Star for confirming my suspicions.

The only immediate change I've noticed is an occasional sudden drop in the idle speed from 800 down to about 500 while the engine is still cold, and cold starting needs the pedal on the floor. I don't think it did before, but I hadn't had it long enough to be sure.

Is there a way to determine what the correct position for that adjuster should be ?

By the way Star, I think that you must have another one in mind. This one was actually given (yes, really) to me by a friend.
I did wonder at one stage if I'd accepted a white elephant(well, pearl grey), but it's such a good ride that I've decided to restore it.
Gave my Citroen Zx to my granddaughter, so I expect this will go to my grandson - if petrol/gas is still available or legal by then

Regards
John

 

[star]

No probs, just i nearly aquired a 190 with a gas conversion 10 days ago, with a gas running problem??

 

[Greybeard]

Perhaps there are lots of them out there.

Should I start a club ?

Regards
John

 

[Greybeard]

Its the throtle venturi stop, not the way to adjust the idle because it'll mess the settings of the throtle venturi switch(which plays up anyway)

ps, nearly got that car, u just beat me to it.

Star, I should have asked earlier but what's the throttle venturi switch ?
Does it have another name, as I can find no reference to it, and is there a way to get the throttle venturi stop back to the correct position, apart from going back to the garage and asking the guy to remember how much he moved it ?

Thanks,
John