The wastegate is involved in the release of pressure from the turbo to regulate the level of boost.
This IS going to happen, sometime. The symptoms can be:
- Lack of boost and power (wastegate stuck open).
- Uneven boost and power delivery (generally sticky).
- Wheel-smoking levels of boost and power (wastegate stuck shut) usually closely followed by fuel cut-off and minimal power for 30 seconds at the most inopportune moment plus illumination of the CEL light and a code 31 - see CEL codes.
Porting the Wastegate
Porting the wastegate involves boring out the wastegate hole so that it is larger and can therefore release more pressure more quickly. This can be important to prevent overboost when a large bore exhaust has been fitted.