91 F150, 4.9L Jerks at gear change
 

When the truck is hot it jerks when changing gears (hard) unless I'm giving it the gas real good. You'd think the back end was coming out from under you. My transmission shop owning buddy says the tranny is fine, put it on a reader and said the TPS was bad. I replaced it, still same problem. Gave it a complete tune up (plugs, rotor, wires, gas and air filters, you name it). No improvement. Problem most often occurs when I am in a slight exceleration in traffic. Like when you first leave a red light, but the traffic prevents you from excelerating quickly, or a low idle roll. Also when I'm turning a corner and excelerate then let off the gas as I'm rounding the corner.
One other old aggravating problem: She's very hard to start when she's cold. Will crank right up, then die. I have to feather the pedal to get her going. Use to crank up and idle high for a minute, but not anymore. Thanks for any help. Clyde