93 econoline audio problem

[buildingholes]

hi..having some issues installing a new pioneer head unit...the sound from the newly installed pioneer 6x8s is popping alot unless i tune everything down very low in volume.. im guessing it is a problem with the factory amp, or not.. how can i find out if my van has a fatory amp.. where it is at.. and what tool to use to smash it to pieces.. lol the factory radio had a few numbers on it i thought might be helpfull .. they are...
f2uf - 19b132 - ca

thanks