Just went to adjust lambda but car would always stall
 

I went to adjust the lambda on my 1988 300SE just now. Readings are a bit on the rich side at 33-40%. I have never adjusted it before but I now have the correct meter and have read many posts. One thing I didn't see is exactly how you turn the adjustment screw. I know you press down and can feel it engage but do you do this while the car is running? Every time I push it down and just engage the adjustment screw the car stalls. I haven't even tried to turn it one way or the other and won't until I get some responses. I've read too many by people getting things screwed up.