Megasquirt: rich idle

Hello everyone,

I just installed a turbo on my 1.6 miata stock internals.

Running Bosch ev14 640cc injectors, ngk-4091 spark plugs and stock fuel pump

Now I have this weird problem that I can't get my car to idle stable above 12 afr.

The fuel map is looking pretty ok to me. Everything above idle, the car runs very well.

I changed the required fuel and injector dead times to the correct values.

Can a faulty O2 sensor or vacuum leak be the cause of my problems?

I provided the tune file and a log of my adle running at 12 afr in a wetransfer link:

https://we.tl/t-D5hAOJkmmX

(the log provided is with the IACV connector disconnected to be sure)

Thank you in advance and kind regards,