My recomendation is to check and clear the boost sensing hose that connects from the side of the intake manifold to a device on the fender.

I had the same thing happen to me after a repair session. This hose is relatively small in diameter, especially the hard plastic section, and is exposed to all the soot thrown into the intake manifold by the EGR valve. If your car is like mine, it ran for many years before the EGR valve managed to malfunction and stop blowing soot into the engine intake.

So, disconnect both ends of this hose and blow through it to clear it. Reconnect the fender side and again blow through it to try clearing anything lodged in the switch device.

Also, run a small wire through the hose fitting on the intake manifold to clear it.

Sure makes a difference in performance when the boost doesn't work. I left my boost disabled for awhile to see what the difference would be in fuel mileage. For me it might have been 1/2 mile per gallon over the course of a tank. Not worth it to go without boost. I guess the turbo gets you up to cruising speed faster.

Ken 300D