I have a 1989 420 sel. Can anyone tell me how to disable steering. It always engages when steering straight when turning key to off. Then wont let me turn key to start. Change the tumbler but it still does it.

Please advise. Thanks

 

Same thing with me, but I slightly turn the steering wheel one way or the other and then the key will turn.

 

It is quite easy.

Here is an excellent write up.

http://home.comcast.net/~chwilka/rep..._lock_cyl.html

The MB dealership have these for about $100.
The new ignition tumbler comes complete with a new key.
The tumbler unit is coded to you VIN.
Extra keys were $15.

 

Did you get a new key with the tumbler unit?
If not get as new key. It might be worn down.