sorry to hear about all the trouble your having. I had a similar issue with a friends supra after 3 weeks of knocking are heads it turns out the hose after afm to hard pipe was thin and weak so it was colapsing from the suction not leting the engine breath. replaced the hose and the car is running great. the only other thing I can think of is a restriction in your exhaust good luck man I hope you figure it out soon
