Remapping a 1.6 HDi / Pulsating acceleration

First of all, English is not my native language, so please ignore my mistakes.
I have a Citroen c4 Coupe , 2006, 1.6 hdi with 90 hp from factory.
Originally this car does not had DPF, Dual Mass Flywheel .
I shielded the EGR, coded out, removed the Cat , straight pipe all the way .
After the remap, and multiple maps, the car behave like this:
When at full throttle, in any gear the acceleration is pulsating between 2 and 3 k rpm. After 3 it's fine. (Its like i'm giving full gas, then 3/4 then full again, not a stable gliding rpm) Somewhat like the pressure is building up, then something is cutting back .
No leaks, pipes are fine, clutch is new, turbo is OK, wastegate closing is normal, vac OK
I've heard that these engines are shit to remap so any advice is welcome.

Thanks!