A Blow-Off Valve(BOV) is a component present in turbo engines with function to release a pressure. It is located right before the throttle body.
Actually it is a vacuum operated valve which releases air to the atmosphere or back into the intake.
It helps to protect our turbo system from 'compressor surges'.
These surges occur when throttle pedal is released while under turbo boost, normally when we changing gear.
When the throttle plate is closed, the high pressure air in the intake system is trapped by the throttle and a pressure wave is forced back into the compressor.
With no place to go, the compressed air will pushes back against the turbo, possibly damaging it.
The Blow Off Valve will react quickly to this situation and release the compressed air.
So, the turbocharger will keeps spinning even the throttle plate is fully closed.
Once the driver presses the throttle pedal once again, the turbocharger - which is still spinning - will keep on providing the optimal power .
