Well it’s official, I’ve gone nuts. I went back to the stock diverter valve location after all the time I spent thinking about diverter valve relocations. The mechanical valve was nice but I wanted ECU control. The ecu controlled relocate was nice but required some rigging to get it to work with the stock intake. So I’ve gone full circle and landed back at a nearly stock intake system setup. My stock intake is back in, and the diverter valve is back in its original location.
Initial impressions are that the D valve feels better in the stock location than in the relocated position. Maybe something was leaking? No logs yet, they will come eventually. Boost response felt a little “off” with the valve in the relocated position. It bogged sometimes and the car felt labored in the very low rpms. The boost ramp up was a little strange, it felt like it would spec too much boost at a low rpm. I should have run some logs but didn’t think of it at the time. With the valve in the stock location, boost response feels better and is more linear.
There are a handful of reports stating that the valve does not seal correctly on the FSI, leading to decreased throttle response and delayed boost peak. The cause was never determined but in most cases the problems were resolved by switching back to a diaphragm version. It could have resulted from a faulty valve or improper installation. My valve seals and functions just fine. The summer heat should really put the valve to the test, we’ll just have to wait and see if it holds up.
I think Volkswagen and Pierburg (manufacturer of the actual valve) have finally come up with a bullet proof solution to an annoying problem (torn diverter valves). The valve is maintenance free and if it proves reliable, is perfectly fine for a mildly tuned 2.0t.