Hi all,

long time reader, first post.

Car is a 1.8T with externally gated GT28 with roughly 14psi wastegate cracking pressure.

On first pull, everything is ok, car pulls as expected.  Then on second pull, rlsol, and hence boost is capped.  Because of the spring pressure, this results in a throttling of the engine.  I have tuned wideband ECU and never had this issue.  Attached the tune, original and log.

For testing, all overboost/underboost etc functions are essentially disabled

Looking at the log, row 562 is a WOT 3rd gear pull and all is normal.  Then at row 669 pull in 4th gear, you can see that rlsol, psol and misol are reduced.  From then on, they never recover to original values.  No knock is detected, zero timing pull, although not shown on this log.

Any thoughts welcome, James.