My problem on my old bronco is that since doing this maf conversion its got a hesitation or pulse over light throttle, so i had a old ford tech take a look at it and we unplugged the map sensor electrical connector(vacuum to be left disconnected turning it into bap sensor) now it runs perfect but my check engine light comes on? i know its because emissions are suffering drastically but why would it run so great with no electrical connection??

 

Solved my problem it was a bad egr control solenoid. Had to be vacuum related...