I’m running FlashPro on my ’07 Civic Si (K20Z3) with the following mods:
RBC manifold
Skunk2 CAI
Full exhaust
Stock throttle body
I uploaded the "PRB tuned" calibration as a base map and adjusted VTEC to 4700, but now I'm getting noticeable idle surging once the engine is warm (between 1000–1500 RPM fluctuation). No CELs, and TPS reads 0.0% at idle.
I’ve already:
Recalibrated the TPS
Done a full idle learn procedure
Checked for vac leaks (none found)
Has anyone seen this behavior before with RBC on stock TB? Could it be related to ignition timing at idle or MAP target?