First of all, thank you guys for the thoughtful advice. I will try to diagnose one at a time tomorrow and let you know what works. I know already that the throttle body has some chaffing (very minor wear) inside where the butterfly meets the body in the closed position. May be a source of leak. Also, this is a very early 230sl but it has both vacuum and centrifugal advance (and electronic ignition...which I installed without effect on this current idle problem). As for the oil level in the pump, I watch it closely as this early model does not have auto-fill. What a pain it is to check, though. I never knew there was an air filter in the air intake for the pump, does this require maintenance?

Now, can someone just get me a get out of jail card if I work on this tomorrow...it is my wife's birthday.

Thanks all,

g
'64 230sl (my reliable car)
'94 E500 (my airport car)
'98 E320 wagon (wife's dog bus)
'04 C240 wagon (kids safety machine)