New here got problem with coolant

[Tuck87]

I got a 1991 Ford ranger ext.cab 4.0 5spd lifted. I got coolant going in my overflow container when motor isn't overheating any idea's and it is also misfiring or bogging.

 

[adsm08]

Why is that a problem? That's what the overflow is for.

As the coolant heats it expands, since you fill the system cold, there is too much in there when hot and it has to have somewhere to go, hence the overflow.