Hi, I introduce myself, I'm Leo from Argentina.
I have a fiat bravo 1.4T multiair 140hp
we're trying to remap it with kess v2
but I have a problem I can not keep the pressure, it falls and the car is fat oil, and change the n75 and the problem continues, the wastegate is fine, there are no pressure losses, the diverter is fine. I do not know what to try

the car has all std, only complete exhaust in 2.5 inches and one intake

load 22 psi drops to 18 reloads 22 and starts to fall again (normal)

any ideas??

Sorry my bad english

The standard turbos can't keep the pressure up in the high rpm's.

I'm not sure, what is the standard turbo on the multiair?
My vl36 can has a max of about 19psi, but then falls down to about 16-17 psi at 6300rpm

Are you sure the n75 is correctly installed?
I had a similar problem when i replaced the turbo i installed the n75 wrong(vacum lines in wrong ports)... the pressure would spike ..go up and down until the ECU would go into limp mode.