Before

After

Boom!
I took a recent trip up to Utah and back and along the way there's several many mile long uphills. I went into limp mode a few times, (key off, key on clears) and read that the 3 most common items could be AFM, vacuum leak or sticking VNT vanes on the turbo.
Starting out with the easy bits I got this in the mail. Oooh nice soft new rubber.

Also, Tim from Don's Repair came down to visit and pick up a car from Copart and helped me diagnois my rattle during braking coming up to a traffic light. (You know Don's is the shizzel for Scooby repair right?)

So check it;
On the shifter linkage cable there's an aluminum heat shield tube. Mine was freely sliding, and most of the time because the cable slopes slightly to the rear of the vehicle it was down in the tunnel wedged up against the underbody heat shield. Under breaking though, this sleeve would slide forward a bit, which allowed the underbody heat shield to vibrate and cause my noise. Temporarily I just pushed the aluminum heat shield tube down, rearward further so it'd be tighter wedged in, but I need to get under there and remove that section of exhaust to properly tighten up the heatshield to permanently fix that issue.