2001 seat leon cupra boost issues

[Pamdam]

Hi i have a seat leon cupra with ko3s upgrade, front mount, ram air induction, removed pcv and installed catch can, 3" decat with 3" stainless cobra exhaust.

the car is not remapped as far as i know and i am having really trouble with the boost levels.
in first it will only boost to between 6 and 10 psi,
in second it will boost to 15 and then slowly drop to 10 psi
in third it will sometimes do as in second but also on occassion it will spike at 20 then drop to 14
in 4th it holds 18psi smooth
5th holds 18psi smooth
6th hits 20 then drops to 15 and back up and down the whole time

its mad i have tried installing a manual boost controller which was fine for a couple of miles boosting 17psi in all gears but then will only boost 5 psi in every gear after that.

any help would be great.

the previous owner of this car did the majority of the mods and when i got it it was shocking everything was bodged together and im slowly pulling it back around.

Also i had to replace the MAF recently as it was running a shoddy aftermarket one so i put a working one from octavia vrs and thats sorted the MAF related issues at least.

I ran a 15.01 on saturday at santa pod with the boost issues which was disapointing.

 

[Pamdam]

Bump

 

[gavalar]

Have you checked common boost leaks/vac leaks?
to be running 18psi must have remap? or cranked waste gate? standard is 7-10 psi iirc?

 

[Pamdam]

In most gear it drops to 10 and in first it's only 6-7 psi then in 5th and 6th it normally 18 and drops to 14-15.
I have an "awesome"dump valve I forgot to mention.
It's not always the same.

I just ordered a new n75 to see if that helps.

 

[Pamdam]

Bump help still needed

 

[Pamdam]

bump!!!

fitted the n75 from a TT 225 and checked for leaks so neither of those are the issue. could it just be the map on the car playing up with the new mods?

 

[Pamdam]

Bump

Could this be a wg actuator problem?