Seem to only get the 30FF CEL come on at a specific time. Usually happens when cruising in 4th gear at around 50% throttle it'll come on and strangely doesn't happen very often. Doesn't happen when cruising in lower gears, under WOT or full boost, always seems to only come on during partial throttle and ≥4th gear at highway speeds. The car does not go into limp mode, boosts fine imo, and runs great. The CEL always disappears after restarting the car. Car is an 08 manual and completely stock with no tune with 80k miles.
Already replaced with all new vacuum lines and both boost solenoids with no luck.
Just wanted to see if anyone here can point out something more specific before I go invest in a smoke machine and/or compressor for a pressure test, and start pulling everything apart.
Thanks!