Ok EFI guys need a little help. 88 5.0 speed density motor, runs perfect and purrs like a kitten until I reach about 60mph, then she surges and bucks.
Any throttle position up to that speed is fine and she pulls hard. I am leaning towards three options.. 1 speed sensor that I swapped out with the new speedo cable I got. 2 coolant temp sensor, or three MAP sensor.
I'm leaning towards the speed sensor because she was running fine before the speedo cable went in. It was a kit from a mustang place that included a new speed sensor with it.
Seems logical to me that she'll pull hard up to that speed and if I let off and hold her about 55 she runs fine..
I guess if that is my biggest bug that is fine with me. Thanks guys!