I just found this:
http://www.k6jrf.com/MB_asr.html
Looks like the NSS can cause a varying idle speed (see down at the bottom of that page). Interesting.
Back to diesel for me
Joking but serious, the diesel engine just works, it's not dependent on sensors or switches to tell it how to run. I like that. If I'm going to drive an older vehicle, I am starting to think that it can't be gasoline powered without some headaches.
How is the upkeep on these older gas MBs? What I'd be afraid of is having to drive with a code reader in the console ready for things to fail and go into limp mode. That sounds pessimistic and I shouldn't jump to conclusions just yet (just got a gas and haven't fixed it yet). But I'm starting to wonder the more I read. But of course this is a fix it forum. The only thing I'll find here are the problems. Maybe I should start a new thread on this specific question. But I'm curious on other's experiences.