Suffering from Low Boost Pressure?

[Ady_E]

I was. (with the emphisis on the 'was') I found the problem to be the 'Boost Pressure Regulator Valve N75'.

I spent ages trawling the net, this forum included, for a decent explanation of how this valve works. (or in my case, doesn't). And at last I found it:

N75 Data Sheet

It also has a good diagram of the whole boost system if you need it.

So, if you're also suffering from Low Boost Pressure, take a look at the N75. Just measuring the resistance of the solenoid coil (should be around 30 ohms) isn't enough though. My valve was electrically sound but was 'passing'. Charge air was leaking through the valve to the output that controls the wastegate actuator thus causing the loss of boost pressure.

Hope this helps anyone else with this problem and if not it might make for interesting reading anyway.

(I have copied this post from the A6 Forum where I originally posted it because the A6 is not the only car the N75 valve is fitted)