I was just tightening my throttle cable, was able to remove about 1/2” of slack. What a difference it makes. However, I noticed it seems there’s a screw or something missing from the area circled in red. Is anything missing or is this actually how it is?

 

I don't recall something bolting there when I had my GS400, it was just an empty spot.

Here's a photo of another GS400's engine bay.

 

Thanks bro! Im an idiot. I googled Lexus GS 400 under hood. Forgot about the term engine bay. Much better results when using that term!