164 improvement not improving performance...

[mfd164@domain.elided]

I just installed a free flow conical air intake from MSDS today on the 164S.
Taking a small step back, I just had the 70K service done, and part of the
work was to figure out the 1223 fault code I had been getting. They came
back to me with "no problem found", although I still get the same code
today. I had noticed zero performance losses due to this, until today. When
I let her rip at full throttle (with the new intake), everything is great up
until around 5K rpm, maybe a little above, depending on who knows what?
Anyway, at full throttle, when the revs get up there, the car loses all
power. I can keep the thing floored, and it will only build revs VERY
slowly. It feels like I have hit a rev limiter, only a helluva lot sooner
than I should. I don't keep my foot down for long when this occurs b/c I'm
scared of something bad happening. The first couple of times it happened I
noticed a good puff of dark smoke behind me, but that ceased (for now
maybe). I can get the engine up to the rev limiter by taking my sweet time
and using little throttle, but lets be honest, that doesn't impress me too
much. I thought about air leaks, but haven't found any obvious ones-
everything seems to be a tight fit. The check engine light doesn't come on
either. Is this a fuel mix problem? Or is my ECU just not catching on to the
change in breathing right away? Any help is appreciated. And happy holidays!
Mark

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