Right when I got home yesterday, I started revving the engine to get a feel of it, since I was planning on giving it the atf treatment. And noticed that when it reached around 1500 rpms when decelerating it would momentarily stumble, like if it was hitting a bump or something. Is this normal. Is it something I should worry about, get checked?
thanks

 

Might be when its joining the dash pot, it slows the rpms somewhat