Not wanting to hijack this thread, but i also think i have a hesitation between 40-60mph, before and after this the car goes like the clappers. I have noticed the whiz from the turbo is quite loud with the window down when on boost. How do you do a visual check for boost leaks? AUM engine 2002
Just do a general look of the pipes, take the engine cover off and have a poke around...
The most common places are under and around the inlet manifold, and a bit of a hidden one is on the end of the inlet manifold, its like an E shaped pipe, it normally splits on the inside, so you cant really see it.
Under inlet manifold hoses are the plague, I have two or 3 leaks coming from that area so it's either the hoses into the Y-Piece suction pump or the suction pump itself. I made myself a boost leak tester which revealed these, I just need the time to strip them as they're all awkward to get to.
By the way since these have split I also have the hesitation however, I am still running on x2 ORIGINAL coilpacks so they need to be done too. Coilpacks seem to die slowly, a stutter here and there then they'll fully fail and thow up the EML. I only had two replace when Mr RAC came out to rescue me.