19mustang86

Help! I have an 86 gt bone stock with 125k on it, recently after it heats up, the car runs really rich and starts bucking like a horse, it seems to be related to heat. After about 20 or so min of driving is when this happens, then the only way to get where I need is to pull out the timing spout, There is a slight loss of power but it will run. it codes 67 and 81, however an 81 says thermactor lol what in the world is a thermactor

thanks for any help anyone can offer