Car acted like trans was acting up from time to time. Then started struggling to gain speed from 45 to 60 or so. Suspected a bad intake and plugs n wires. Changed lower intake gasket and upper intake manifold. Put in ac deco iridiums and wires. Cleaned throttle body. Now car Boggs down all the time not just in the 45mph range. Suspect whatever sensor was on its way is done now. If I rev it up slow from under the hood it runs very smooth but if I rev it normal it sounds like its drowning. Anyone got any ideas? I am stumped!