correct idle rpm
 

I have a 500sl - 1986 - it idles at 400rpm once it is warm and in drive. during warm-up it is a little over 1000rpm. is this within acceptable parameters.

it feels like it is a hair away from stalling, though it never has

also, the oil pressure gauge once it is warm fluctuates around the 2 level. goes right to 3 upon acceleration.

generally, rpm at idle is within 600-700 range.
400 for sure is low. my car sure shakes below 500
and subsequently dies.

there is a long list of possible causes, but would suggest
a good fuel injection cleaner. good luck!

thanks - it does get a little shaky under 500 - added some techron yesterday - will see how it works out.