Are you sure the blow off valve isn’t causing this? What kind of BOV is this? Is it spring rated or is it a pull type (HKS Super SQV)?
And have you tried without the BOV?
These are the O-rings needed for the Aircon system
80872-ST7-000 = O-Ring (1/2") (needed for aircon condensor)
80873-ST7-000 = O-Ring (8mm) (needed for aircon condensor)
I had the same sort of spots and used Iron X to remove them. Spray some on, After a couple of minutes I used a brush to clean it and after that rinsed with water. And everything was gone. Btw I had it all over my freshly painted car [emoji30]
You can unplug the switch and test with a multi meter if the switch is not broken. But it looks like it is wired wrong and connected to the 12V instead of the switch output of 12V
Could it be the throttle body? The butterfly valve which doesn't seal correctly or maybe a bad gasket between the throttle body and intake manifold.
You can re calibrate the TPS 0% and 100% setting in K-manager. Maybe do a datalog to make sure the TPS is reading correctly during a trip. If you...
Are you sure you have no vacuum leak? As you said you replaced the intake manifold. If there is a vacuum leak the car hunts/bounce also to 2000 RPM.
Just use some brake cleaner and spray at the vacuum hose connections. If the car revs higher you have leakage on that part ;)
Just with the engine running make 3 times a full lock left and right with the cap of the reservoir and all the bubbles should be out of the system. Keep an eye on the level while doing it [emoji6]