Notchy steering question
 

77 911s. A little hard to describe, but after turning left from a stop light today my steering did not want to come back to center, I had to pull it back. It felt like it had stuck in the turned position. I am just learning about the steering components so do not know what would cause this. Where should I start.

Thanks in advance for replies.

PK
77 911s 2.7 cold climate car with no usual issues
88' 635 Csi
533i x2

PK -- have a search on this forum for steering universal joints.
Might be the rack itself, but the universals are an easy lube.