2008 dodge ram 1500 5.7 check engine code pz452
 

does anybody know if a bad charcoal canister would cause my gas tank to take gas slow when filling up? nothing is pinched or bent.

Yes. As well as:

Failed fuel tank pressure sensor
Harness to the sensor has an open or short circuit
Faulty electrical connection to the FTP sensor
Cracked or broken vapor line to the vacuum canister
Cracked or broken positive vapor line to the tank
Plugged line Leaky gasket at the fuel pump module
Gas cap left loose resulting in a loss of vacuum
Pinched vapor line

i"m trying to narrow this down and start with the cheaper stuff first. Gas goes down filler tube super slow. nothing is bent or pinched in the filler tube or vent line. i dont think a pressure sensor would have anything to do with the tank not venting. I just dont know what to try first. the charcoal canister arent cheap for this model

Charcoal canister shouldn't have anything to do with it either. That's just for vapor recovery. There's gotta be a clogged vent there somewhere.

When my truck did this it was the rubber hose from fuel tank to metal tube leading through fuel filler neck ,,the rubber line was twisted somewhat from dropping fuel tank for new fuel pump , after raising tank back in place I had to loosen clamps on rubber fill lines after install an twist lines back in place were the kink was gone an flowed like new afterwards ,,if you haven't had tank off then one of the lines to filler neck could have collapsed one of those lines are most likely the issue I would think as it has to breath for fuel or any liquid to flow properly in to any type of enclosed tank .