Hi all...my 99, 4.6 bogs when I approach any kind of incline going between 60-70 mph...it runs perfect idling or if im driving on flat roads. There are also no check engine light going on.
I was thinking maybe a clogged converter, & hoping maybe a bad plug!!

Thanks all Ive been on here a few times with questions & always get great advice....

 

Another case of one or more bad coils / wires and/or plugs.
Do a full tuneup of plugs and boots and fuel filter. If still present, suspect the coils.
The fault get's noticed when the EGR is operational, the fuel mix goes lean and the plugs can't fire it.

 

look into fuel pressure.