Re: Do you know when your supercharger runs?...ALWAYS
I've never inspected the internals of a screw-type supercharger, but I assume it is made to very tight tolerances. I do know from tinkering with carberators how quickly an engine loses power if you choke or throttle it. It would seem that a non-functioning s/c must really choke an engine at any rpm above idle. I can see the logic supporting waldig's findings, since our engines have power at any operating speed.
Brianbrave, as for boost or vacuum readings on your gauges, maybe the position of your sensor determines your reading. Upstream of the intercooler you might get higher boost readings because of the restrictive nature of the cooling passages. Downstream from the i/c you might read negative pressure because the throttle plate is wide open and the pistons are sucking air like crazy but the i/c is limiting the supply. The dynamics of the system are a bit beyond me, so this is just a theory. There are a number of you who would know if it has merit or is just caca.