I installed a 75 mm tb and plenum by accufab. car idles fast then slows down sputters like its going to die so I shut it off. I have read about adjusting the tps sensor But Im not sure how to do it.
i would do a search for adjusting the tps, with the accufab combo it said you shouldn't have to adjust it though my car acted really weird but i got it tuned right after and it ran much better, thats after the tps broke on the dyno lol
check for a vacuum leak first....that was my problem when i put mine on
try and listen for an air leak...use a rubber hose and run it all around the plenum with the other end in your ear. i found mine at the egr valve, and had to mess around with it for a while to get it to seal.
Check that all your vacuum hoses are connected on your upper plenum (correctly). My Accufab installed perfectly with no adjustments to the TPS. My Accufab idles perfectly at 700 rpms (after warm up) and is smooth as butter. It's gives me an erection it is so sweet. I seriously doubt you need to mess with the TPS after all I went through.
Accufabs are one of the best if not THE best TBs...