Hi. İ own a Alfa 147 1.9 JTD 16v. The problem that İ have been getting the code PO237. This problem appears when İ drive my car more than 160kmh. After 160kmh the car goes on limp mode and the check engine light comes on. When İ stop the car and wait for like 10 mins the car resets itself and it's not on limp mode but check engine light will remain and İ have to clear the codes out. İ have changed the map sensor and İ have cleaned the turbo. What can be the cause of this problem ?