TSP seems unlikely. Warm the car up really well and take off the cover on top of the engine where the throttle cable attaches to the linkage. Take off the cable. Operate the linkage and check if the linkage to the butterflys is binding on the metal hose that comes off of the front valve cover. If not, it is possible the butterflys might be binding but that is rare too. You can mark the location of the TSP and take it off too to see if that is your problem.
