Focus ST/RS Boost Solenoid
The Ford boost solenoid is a common "wear and tear" item,
You can detect if you need a replacement when your car starts to loose response or hesitates when driving or if boost levels are dropping. On the other end of the scale, if you are getting boost surge issues, the solenoid can also be to blame.
Can be fitted DIY but access from underneath is required
£74.99Price