my 1997 F150 4.6 V8 will start fine and drive fine but when I
brake out of acceleration and brake for a stoplight the rpms will shoot
down and the engine will start to bog usually it shoots back up but most of the time it stall (never when drivung)

 

Sounds like your Idle Air Control (IAC) valve needs to be cleaned or replaced.

 

Yup, IAC most likely - Pull it off the TB elbow, hit it with B-12 and blow it out asap (don't let it cook) - Chase it with WD40 , Work the movable parts inside a bit - hit it again with compressed air to force lube the tight spots, you can hit with WD40 one more time and let it soak this time , it prolly wouldn't hurt. Then blow it out , make sure everything is still working inside.. That's it , should purr like a lizard.

 

thank you alot I will try it