Reddit mentions of Genuine E3D V6 Silicone Sock Original 3 Pack

I'm assuming that you are not using a silicone sock. If you are not, stop trying to print in PETG until you install one. It's just not worth the headache until you have the right setup.

Get this version of the sock, not this version. The sock prevents the material from blobbing around the nozzle. Blobs around the nozzle inevitably cause problems. The material hardens and then chars, and then is likely to collide with layers below. Or the blob will peel up one of the first layers, so that your print is ruined before it even starts.

Using the sock also helps stabilize the hotend temperature when using the fan, and so may solve the problem you are having using the default fan speed. You should do a PID tuning of the extruder heater after installing a silicone sock.

There's a couple of tricks I use to get a PETG print started: For the skirt (not brim), I use Slicer to change the skirt in three ways: First, I make the skirt only 1 layer high. Second, I make the skirt 3 or 4 perimeters wide. Finally, I keep the skirt at least 20 mm away from the print itself. Making the skirt wider on the first layer gets the nozzle into a steady-state where it tends not to blob as much. I make the skirt only 1 layer high because if there is a blob on the first layer, it can catch on the nozzle when the second layer is printing and get pulled up, ruining the print. Finally, I print it far away from the print itself because if the skirts lifts or strings, there's still a chance that the print itself will be OK. This has improved my success rate with PETG a lot, to the point where I almost never have a failed print.

There's one more thing you can do if you print with PETG a lot. I stole this from another Redditor and don't remember who. It's a change to the Slicer gcode that keeps the hot end at 160 C until after the bed leveling, and then heats up the nozzle just prior to the purge. That greatly reduces blobbing as well. But for it to work well you should still use a sock.

Here's the start gcode I use with PrusaSlicer:

G90 ; use absolute coordinates
M83 ; extruder relative mode
M140 S[first_layer_bed_temperature] ; set bed temp
M109 S160 ; Set extruder temp before bed level
M190 S[first_layer_bed_temperature] ; wait for bed temp
G28 W ; home all without mesh bed level
G80 ; mesh bed leveling
M109 S[first_layer_temperature] ; wait for extruder temp
G1 Y-3.0 F1000.0 ; go outside print area
G92 E0.0
G1 E8 ; Purge Bubble

The soft flexible cover on the hot end is called a silicone sock: Genuine E3D V6 Silicone Sock Original 3 Pack https://www.amazon.com/dp/B077TKBKR3/ref=cm_sw_r_cp_apa_i_U86tDb9E88C39