Transient timeout errors when Publish / Schedule

I’m getting transient timeout errors on my blog. It seems to happen only when I Publish / Schedule. Then sometimes, it hangs, I get timeout, but the post is there as it should be. The rest of the site works fine. The problem is transient. My host says they see nothing that could be a problem.

I don’t think it’s plugins and Google Page Speed gives it a 92. I’m thinking maybe it’s a borked index but not sure how to check or fix it. MySQL check table reports no errors on the tables.

Ideas and feedback would be greatly appreciated.