Range rover l322 3.6v8

P023D-22 is overboost, which can be as a result of turbo actuator rod rose joints binding, gimbal plate sticking or a small charge air leak causing the boost pressure to be improperly regulated. Unless you can read live values or smoke test the air inlet & charge air ducts for leakage, you're not going to be able to make progress. At this point, we're going around in circles.