Yes, my ignition springs back about 10 degrees. The spring isn't really strong but it does pop back a bit when I release my fingers. I guess the car would keep cranking if there wasn't a spring in there.

My tumbler was replaced by the PO. Just checked the paperwork. Maybe that's why mine is still fresh.

I changed out the locking mechanism on my 240d. It jammed up so I pulled the tumbler core and started it with a screwdriver for awhile. I don't recall the spring being in the switch portion. I think it was in the mechanical monstrosity that locks the column, cuts the vacuum etc. Mine was binding on a little cam inside and it jammed up.

I ended up getting the entire mess - tumbler, locking mechanism and switch off a guy who bought the wrong one for his 300sd which happened to fit the 240d. Nearly new for $200.

I recall looking at Kent's info and his tip at the time was changing the tumbler which was not my problem. I used my old tumbler to keep my old keys. Its a common failure point but in my case it was the mechanism in the column being worn and binding.

The big wake up call in his thread is how much current that circuit carries. 8A is a lot to run through all those multiple barrel connectors and switches. The contact resistances must be low or you're going to get big voltage drops.

I guess it is pretty good design because look how long it lasts. My 1999 Accord went through three ignition switches in 106k miles because the contacts in the ignition couldn't carry enough current and burned.

Edit - I will defer to Funola's explanation of the spring being in the switch. It has been too many year since I had those parts torn down on my bench. (2009?)

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 190k miles
97 C280 150k miles