Hestitation / Studdering at high RPMS

[Boosted98RS]

I went to test drive this 1st gen awd today and it seemed to hestitate / studder as soon as it hit around 6-6.5k. The owner didn't really know what it was. I'm thinking bout buying it but wanna make sure its nothing serious? Only mods is a 2.5" straight through exhaust, it had a boost controller on there and he thought it was hitting fuel cut, me also. But he took it off tonight and said it was still doing it? I was thinking it was either the TPS or coil pack could I be right? Is it a simple fix or should I think bout something else? He said he needed a new coil pack and it was pulling that CEL code so I was thinkin it was that but would it only do it at that high of an RPM and idle / drive normally besides that?

 

[dbritt]

I don't know much about whether or not if the coilpack would be the problem, but I know that I used to have the same problem because it was running too lean. I just turned up my AFC about 10% in that RPM range and it fixed the problem. If you have a datalogger, hook it up and see what it looks like in there.