bronco-up

I have a smooth running bronco 5.8 when i accellerate at its own leasurely pace, but when i want some power off the line, it wont give it up, until i reach approximatley 45 mph, when the problem, whatever it is, goes away and the car takes off like hitting a nitro switch. My shop says it may be the throttle position switch. I will check the codes (my first time doing this) but wanted to ask if there should be anything obvious i might check. thank you hull.j@worldnet.att.net

 

LunaticSVT

I would check the TPS.