250 for PETG

This is quite toasty, at least for the PETG I print. I’m usually at around 240 for my first layer and 230 or 235 for all subsequent layers.

Have you run a temp tower?

I haven’t messed with the extrusion multiplier, do you have any information about that?

ellis3dp.com/…/extrusion_multiplier.html for more info. In a nutshell, you lower it for oozie filament and increase it for more viscous filament. For PETG I lower it some, but the exact amount varies by filament brand and color.

That said, I don’t think this is your issue.