Hesitation in my Toyota truck 1991

I have a 1991 toyota pickup truck automatic with the 22 R motor it has 70000 miles on it and I have a bad hesitation problem with it.I had it tuned up last spring at the dealer they did plugs wires valves adjusted valve cover gasket throtle bodie service cost 550.00 still did not cure all the problem. When it gets cold it worsens and in the warm weather it runs better you haveto let it warm up until the temp gauge is half way to nomrmal or it runs terrible until you step on it to the floor and the it takes off great then it runs ok until you shut it down and if you start it up it always starts and go slow until you hit the road when you step on the gas it falls on its face but it dose not stall it will gain speed a little at a time until its at speed but if you smash it to the floor it takes of perfect.