I just put a 75 mm by bbk and i think i put the throttle position sesior on wrong it won't downshift when you mash the gas Is there a special way to install it ,also the check engine light comes on please (help)?

 

Your TPS can be adjusted. with you key on ACC.(not started) take a volt meter and place it on DC VOLTS. Insert the lead into the center wire and the other lead on a piece of metal for a ground. you should read.98 volts. If you do not losen the bolts and move the tps up and down. you should see the volts change. when you reach .98 secure the bolts. I hope this helps

 

Check out this sight
http://www.fordtruckworld.com/forums/topic.asp?id=95443

 

did you (port match) or hollow out the upper intake elbow so it's the same size as the 75MM ?...if not your T/B isn't very effective...also did you reset the computer after the install so it will re-learn the idle point and other parameters?..yes these are basic questions but its a good place to start...the only reason i ask is because i see your new here ...WELCOME....