THe BPV ACTUATOR MYSTERY REVEALED

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 so big.(that's what she said) 


Construction of the BPV consists of a electronic motor that rotates, this then operates a linkage arm which conects to a butterfly valve which is on a rotating shaft. As you can see in my video here the constant movement of this butterfly valve wears out the bearing and causes various DTC. 

Unfortunately this bearing is non replaceable and as such will req a new BPV.


It's smart for a reason.


This electromotor isn't your normal motor and is quite sophisticated when it come to control functions.

 Not only does this smart actuator have a fail safe position just like the VTG actuator it also carries out a sweep before operation to check it's end stop limits but the BPV doesn't require programing after fitment 

Like all smart actuators this is controlled via E-can and belongs to a engine fuse group at d400.

The BPV actuator has various inputs and output such as : 

  • electromotor current

  • Electromotor position
 
  • Outputshaft position

  • Power supply voltage
 
  • ECU temperature

  • ECU hardware and software.





 

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