I have had some boost issues, no boost sometimes then full boost then half boost. Did a scan and found N75 open circuit. I took the N75 out and tested it will a compressor and 12v, when I apply the 12v the air gets diverted back towards the TIP, no voltage air is diverted to wastegate. There is also power at the N75 plug. Weird thing is its only seems to be a problem when things are hot underneath the bonnet. Would an ultrasonic clean do anything for it and some heat protection or relocation? Or is it in need of replacement?