The Weekly Waffle

Let's talk back pressure valves  Following on from my diagnostic and replacement here. We can waffle this week about the BPV or Back Pressure Valve fitted to DAF Mx-11 and mx-13 engines.  Once apon a time we use to have the exhaust brake and it's only job was to create some back pressure on over run.  How things have changed! With the introduction of euro 6 came smart actuators such as the VTG (you can find a bit about that here ) the EGR and the BPV. Now tasked with a multitude of different operations the BPV must now assist the PCI ECU in different operations such as: warming the engine up from cold achieved by creating a lower opening percentage of the butterfly valve. Assist and work in unison in creating backpressure for the EGR valve  Decreasing exhaust gas flow in the EAS system in order to heat up scr and the dpf element Adapt pressure situations in the turbo for better turbine rotor control.  create back pressure for engine braking.  Why is it s