I have the Dr Speed intake. I bought it used way back when. Today, I would just get an intake off eBay. It's just tubing. Pplease don't go to Home Depot and buy PVC Pipe for an intake
Your trans issue, sorry to say, but mine had the same problem, the fix was a new transmission.
It sounds like the electronics inside the transmission. They are way in there and it's like $700 in labor just to get to it, then the part, if you can get it, is a few bucks as well.
I was happy though because I swapped in a GAGT Transmission. I see you have an 02, so you are limited to a trans upto and including 2003. In 2004 the trans pump was changed, and nobody knows how it reacts to pre 2004 programing