So I did a few pulls this morning while it was still cool outside. While doing the 3rd gear pull, the car "bucked" almost like a backfire, but there was no audible sound. The car's power (horsepower) went completely dead and eventually recovered. This has happened only 2 other times all during 3rd gear pulls. Any possible thoughts of where to start? The CEL flashed temporarily, but went off.

The other thing I've had been dealing with was a P0172 - Fuel Bank 1 too rich. I had it back to Buschur to have him rescale the injectors and it seemed to be fine. I did get that code back yesterday. Cleared it and it hasn't come back. Not sure if an injector might be causing this. If so, would it still be a scaling issue or possibly a bad injector(s)?

Lastly, when I got the car back from Buschur's it was dyno'd at 391whp @ 26.5psi. Using VDR, my #s were really close at 383. That was back on Feb 2. Now in March when the weather turned nice, I started to do some more logging/pulls and my whp #s are now consistently around 343. Would this be a good indication of a boost leak?

Car has:
Walbro pump
3" Turbo Back Exhaust (with high flow cat)
UICP and LICP
Buschur's Race FMIC
Buschur's 84mm intake pipe/filter using MAF
FP Black - Ported
Buschur o2 Housing
Ported Stock Exhaust Manifold
Ported Intake Manifold with 65mm throttle body
Precision 1000cc injectors
HKS 272 cams

 

possible that one or more of your injectors can be staying open and causing your fuel maps to get really rich. Have you pulled the plugs yet? That will let you know how the fuel is being burned.

 

^^

Nope, but I can certainly do that.

 

Pulled a few today. Bit of carbon build up with only about 1k miles on it.

 

Check your Vacuum lines. Could be one or more that popped when on boost. The usual suspects for me are EGR lines underneath the throttle body.