Possible fault causes
- Charge-air cooler or charge-air line(s) (on pressure side) between turbocharger and engine leaking
- Charge-air cooler or charge-air line(s) (on pressure side) between turbocharger and engine constricted/blocked
- Diverter valve does not close (sufficiently)
- Wrong value from boost pressure sensor on DME control unit
- Boost pressure adjuster fails to adjust (sufficiently)
- 1 turbocharger blocked/faulty