I got up early and headed to the airport to fly Young Eagles - a couple didn't show up, but we had lots of planes so I ended up flying 2.
After we'd run out of kids to fly, a pilot from Sutter asked to go up in the gyro. We were climbing out when the engine sputtered so we turned back - it didn't stop, but I didn't want to wait for that to happen. I called to say I was turning back to land downwind, and later John told me he thought it was funny when I told the guy on finals that he was going to be going around - he didn't seem to have figured that out for himself.
Anyway, after lunch I decided that it could be the throttle position sensor, as that controls the wastegate via the turbo control unit. That wasn't it - I aborted a takeoff when it happened again. I ended up just going home to think about it. Talking to Don, he's had the same problem with his Sportstar Max (same engine) and it was a vacuum problem, so I went back to the airport and looked at the vacuum hoses - you really want to take them off to blow through them, and that's likely to tear them anyway so I just started replacing them all. That was when I broke a plastic T fitting, so I gave up and went home via Autozone to buy a new one.
In the evening we went to Randy's and watched "The Adam Project" on his projector in the back garden - it looks like summer's finally got here :o)