I found what appears to be a missing cover on the front of my steering rack. Looks like something fell off. Should I be concerned? If it's a missing cover, any idea if it can be purchased separately or would it only be available with an entire rack?

 

You are missing the "Rack Housing Cap"

 

I had this happen once on another car.

Measure the opening carefully with calipers. Go to a good size auto parts store and ask to look at their "Dorman Plug" display. There are drawers and drawers of various sizes and styles of plugs. Find one that fits. As I recall I used one for a cylinder block freeze plug opening and installed it upside down.

First off. See if their is a part number for a replacement from Toyota or Lexus. Doubtful.

Clean the area with a rag. I put some grease in their for the bearing. If you need to, swedge the cap into place or otherwise secure it. It is not easy to get it right, but the cap is necessary.

Loren