[Roger 911]

I'm resurrecting this thread because I bought the 951 previously owned by the OP, dkahler (Doug). Kind of a funny story, but Doug lives down the street from me and we are now in frequent contact, in a good way! This is extremely helpful, being able to ask him what he did when, why, etc. having said that, neither he nor I have been able to resolve the intermittent power cut out at high revs. If you go back through this thread, you'll see that Doug has replaced or tested virtually everything that is commonly referenced as having any potential to impact this issue. I just recently replaced the coil as well.

To recap, here is what I am currently experiencing.

- If you were to drive this car like my wife, you would never know there was a problem.
- If you give it full throttle and let the revs climb past 5K, that's when the problems can occur. Sometimes you get a little hesitation as the revs climb into the 5-6K range, other time it will completely shut off at 6K.
- It appears to be related to the boost pressure. When I cranked the boost down to 5 psi, it seemed to stop.
- I set the regulator now to achieve around 11 psi of boost.
- I noticed sometimes it seems to achieve this boost level, but other times it does not. I understand that 4th gear is probably the best gear to test this in. Unfortunately, there is no where other than a racetrack to safely test this at 6K in 4th gear.
- If I put it in 4th and give it max throttle, it seems to hold the boost steady up to close to 5K (as high as I have gone).
- If I give it max throttle and let it rev in lower gears, sometimes (not always) I've noticed that the boost goes up, then actually begins to decrease as the revs rise. Falling from 10 down to 6 psi by 6K. This seems odd to me.
- The other thing that is going on, and may or may not be related, is the AFR changes. Sometimes at idle, it reads full lean, then other times it stays full rich. Then others it bounces back and forth. When it goes rich, the idle also increases by approx 200 rpm. The O2 sensor is relatively new. Similary, the AFR will sometimes read rich under part or closed throttle. Then other times it will change from rich under part throttle to lean at closed throttle (more of what I would expect).

About the only thing left to replace is the turbo itself. I certainly appreciate any thoughts.

Thanks.
Roger