Hello this is my first post on the forum so bear with me, but my 2003 Passat has a stage 2 ecs tune. I believe it’s ecs not entirely sure, but it’s definitely a stage 2 I swapped it from a 2000 Passat where it only made 10lbs of boost consistently but occasionally would hit 20 and creep down to 10 as I neared red line. I put it onto my 03 and it made 18 lbs for a couple days then dropped to 10 lbs. I’ve scoured the vacuum lines for leaks and have found none, I’ve used maf cleaner and cleaned all of the sensors in the inter cooler piping and manifold/throttle body to no avail. I recently put a k04 hybrid on with a brand new waste gate that operates perfectly so it’s not the wastegate. I currently have an mbc on but I hate the way it boosts so aggressively and even the mbc has trouble keeping the boost above 15 for very long, I completely lost and any help would be appreciated greatly.