Hello all,
I dunno if it's the right place to ask this but am having a weird issue.
I have a 1999 GTI MK4 with AGU (ME3. engine, which is under the process of receiving a complete 2003 20th anni loom (ME7.5).
I managed to start the car and everything seems ok except a rough idle with various DTC errors due to missing sensors which will be tuned out.
My target is to have some logging prior to some mild tuning as I am new to this world, I can scan all modules with no errors while the engine is off, but as soon as I start the car VCDS disconnects and sometimes when trying to connect to engine module the car stalls.
I have tried Galetto 1260/ME7Logger combination but same stalling issue.
Can anyone with prior experience chime in and point me to the right direction? I have tried looking on the web but couldn't find anything similar to this issue.
Thanks in advance.

^ That.  Run a separate k-line.  Disconnect the cluster once the car is started and then attempt to connect.

You need to disable the others too.  Try my solution first.  If you run a seperate line, the ECU needs to connect to the cluster first, and when its running you need to activate your spare line and remove the rest from the system.

So, start the car with normal k-lines.  When running, cut the ECU and OBD k-line and run a new ODB to ECU k-line.