1.8 IS20 Unitronic P0234 Overboost

I have a 2017 Golf Sportwagen 4Motion DSG with an IS20 swap and supporting hardware. I have Unitronic IS20 software, and under certain conditions, I get an EPC light indicating a P0234 Overboost error. This happens when I am cruising at moderate speeds and then give full throttle. My Wastegate is properly adjusted. I am unable to create logs with VAGCOM that Unitronic is willing to work with because it is an erratic error, happen 1/3 times and never when I'm logging.

I have captured what I believe to be a different problem, during the below log it felt as if the car was knocking badly three times in a row. This is not the usual error or feeling when the P0234 Overboost error happens, but may provide some insight.

https://datazap.me/u/8055wagen/p0234-overboost?log=0&data=0-1

I am working on getting better logs for Unitronic, but my time is limited in the summer for logging sporadic issues. Naturally the error never presents itself while I am logging.

Has anyone experienced something similar, or have any suggestions?

That looks awful. When did this start happening?

And can you relog with charge pressure actuator: specified position as well? I think there are vcds limits to number of things to log so drop the 2 torque fields.

Also, your o2 sensor is not looking so hot. Let's see a 3rd gear romp adding the above and importantly the lambda data.

If you want to try something. Loosen or tighten wastegate a bit and run adaptation again. Target 3.5 or 3.7. Wherever it is sitting now at light throttle it is unhappy with. It might be dying and need replaced. Let's see 3rd gear romp first.

Thank you for the response Diggs

This started about a month after I tuned, once ambient temps rose above 60*F, May 2019. I have probably gotten the EPC light 30 or so times trying to diagnose this. Again, the above log was the worst case I have had. Usually there is little to no knocking, and the car goes to limp mode immediately. For some reason in that above log, it knocked hard three times in a row. This has not happened since.

Log from a launch without an error
https://datazap.me/u/8055wagen/launch-data-set-unitronic-s2-is20?log=0&data=0-1-2-3-4-5-6-7

Here are logs in the format requested by Unitronic. I recorded these style logs multiple times and could not replicate the error code / EPC light.
https://datazap.me/u/8055wagen/first-data-set-unitronic-s2-is20-boost-torque
https://datazap.me/u/8055wagen/second-data-set-unitronic-s2-is20-fueling
https://datazap.me/u/8055wagen/third-data-set-unitronic-s2-is20-timing-maf

I originally had a 42 draft design O2 spacer on the secondary sensor, that is now removed. I inspect and adjust the wastegate this weekend, and attempt some more logs if I have time. The wastegate has approximately 9000 miles on it. I was previously JB4 tuned without issue. JB4 is now uninstalled.

Yes, saw all those last night. Those were from May. Need a new run in 3rd. Post cat sensor is not the issue here.

After a month I finally was able to record some good logs. Haven't had the P0234 error in the last few weeks, but I haven't been driving very hard. Hooked up my JB4 again as the VCDS was too difficult to log with consistently. I am going to be sending these to George and see if he has any recommendations for me.

Will update as I work on this

Three logs on the following page.
https://datazap.me/u/8055wagen/uni-is20-jb4-map0?log=0&data=1-4

Initially I see that the ECU request boost is about 3/4 psi lower than the actual boost. I do not know the cause of this, insight would be appreciated.