Some engine controllers measure static pressure under the engine cowl. Measurement in this area may have a very low risk of calibration problems due to common mode threats e.g. insects, their nests, volcanic ash dust, water and ice.
Calibration of these sensing locations is though a complex issue due to variations in (performance of) cowl ventilation inlet outlets over the flight regime and pressure variation due to pneumatic starter motor exhaust and thrust reverser operation.
In recent years, higher bandwidth digital data buses (ARINC 664) have been used to provide engine sensor data measurements and validity (calibration threat flags) back to the aircraft. I believe that this data is used to determine whether the aircraft sensor data is itself out of calibration (e.g. due to ice) I do not know of any aircraft that today use this data for its instruments.
As long as the engine sensor data calibration threats can be managed, there is no reason not to expect more usage of these data in aircraft systems in the future, though the costs of such systems complexity need to be overcome by some overt safety or commercial need.