Howdy,
My 2001 GTP (150k miles), all stock, is running rough - esp on cold starts. Buck / surge, feels like a faint random miss. About a year ago (10k miles or so) i replaced all the intake gaskets, plugs, wires, etc. Last night i changed the spark plugs again, did not fix the problem. I've got HP tuners, and it shows no codes (other than one relating to the EBCM being bad). I can't see any vacuum leaks, i replaced the EGR a few months ago. I'm running out of ideas and about ready to sell it.

On the advice of another:
LTFT - good call, went and played around. light cruise = +16.4 maxed (red) and idle is -10% or so. KR shows up on heavy acc.

For a bone stock car this tells me something is up, what that is i'm not sure yet - fuel pressure reg. problem?

I checked the vacuum lines, did find a few small cracks, nothing major and fixed them earlier today (fixed before logging data).

Any advice on something to check?

Thanks,
James