I have a range rover with the ajv8 4.2 supercharged engine and i made the decision to replace the front pulley with a powerhouse 10% extra performance pulley! However since the extra performance and new pulley has been fitted i keep getting air pressure sensors to high for the air entering via the supercharger! has anyone had issues like this with this engine as i believe most people say this mod is a must! however i am thinking it created an issue! whats your thoughts guys? many thanks

 

Changing the pulley, without changing the corresponding engine tuning, is a waste of time and money.
So yes, you have messed with the parameters of the input to the car. And yes, the car is compensating.