hard to say, if it has failed open circuit or short circuit.

as both the ACt and ECt are NTC sensors (negative temperature coeffiecient - ie the resistance goes down as the temp goes up) if it failed open circuit it would think that the boost temp was low all the time and would never knock back the ignition to limit power, if it failed short circuit, then yes, it could tell the ecu to hold back all the time,

eddited to say,
i have not known a ACT sensor fail on either of my cars, but eh ECT one has yes.