The brief
Farina's Beetle was losing power on and off, fine one minute and flat the next, so she brought it in. An intermittent power loss like that on a turbo engine usually points to a boost leak, air escaping where it should be going to the engine, and that's worth chasing because a leaking pipe only splits further and the running gets worse. The turbo pushes pressurised air through a set of pipes and hoses, the charge pipes, on the way to the engine. Those pipes flex with every gear change and heat cycle, and over the years a hose hardens and cracks or a joint works loose, so boost leaks out before it reaches the cylinders. The car feels flat, the engine management can throw a boost or fuel-trim code, and because the leak can open and close with temperature it comes and goes. A split pipe doesn't reseal, so it gets replaced.
The diagnosis
We ran a leak detector over the intake and boost system, which pressurises it and shows exactly where air escapes, and it found a split charge pipe bleeding boost, which is the intermittent flat feeling. The turbo itself, the wastegate and the rest of the intake held up fine. That's a charge pipe replacement and a recheck of every intake joint, rather than chasing a leak that opens and closes with heat.
The work
The split charge pipe was removed and a new genuine VW-spec pipe fitted with fresh clamps and seals, and the rest of the intake and boost joints checked tight while it was apart. The system was leak-tested again to confirm it held pressure with no escape, any boost or fuel-trim fault cleared, and the adaptations reset. A road test confirmed the power was back, the boost coming on cleanly with no flat spot, and steady through the rev range.
The outcome
Full power back, clean boost with no flat spot, the running steady, no warning light, and the intake holding pressure. The Beetle went home pulling properly again. A split charge pipe only gets worse and drags the running down with it, so finding it with the leak detector and replacing it fixed the power for good.