G code help with AMS filament changes

Hey all, running into an issue with filament changes. What I’m trying it do it use PETG and PLA as support interface materials with each other but running into an issue. At the standard purge amount per filament I run into “soft” lines in my prints at every swap. I can tell it’s the PETG or PLA not being fully purged and then mixing in the layer. This causes weak points on the prints.

My thought was to increase the amount of purge material but am now running into a different problem. When I increase the amount I see the tool head sitting in one spot dumping filament like crazy. So it fills up the purge shoot and then in some instances goes all the way to the hotend and 70% of the time gets stuck in the hotend. The toolhead goes to do a wipe knocking the filament brick either off and onto the print bed or knocks it somewhat loose and the toolhead drags it all over the place hitting into supports or small parts causing all sorts of issues. I’ve even had it knock the cover off causing a stoppage in the print.

My thought was to change the gcode to purge 1/4 of the material, shake it off, do the other 1/4, shake it off, etc until I get to the amount I want to purge that way it doesn’t create this massive filament dump and then try to get rid of it. Looking at the gcode I can see the filament purge area but I am unsure of what to actually change. Would anyone be so kind as to explain what the gcode in that area actually calls out? Or if it’s easy help me write the code to accomplish what I need?

Thanks in advance!!

See this thread from last year Multiple poops with high flush volume please

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