Sensor and learning context
MS4X describes narrowband pre-catalyst sensors for MS45.0. It states that trims learned in closed loop also affect full-load fueling. MS4X reference.
Record sensor type, feedback state and learned corrections with each log. For evaluating an enriched mixture, choose a measurement that can quantify the relevant lambda range and record its calibration/readiness. Keep the measurement separate from a target shown in the editor.
Definition coverage
At the cited revision, MS4X lists 456BO02S for E83 (X3) and E85 (Z4), explicitly excluding E60 coverage from that definition set. The formats are 116 kB partial / 1024 kB full. MS4X reference.
Preserve the exact ID, including letters and zeros, plus chassis and file basis. For another application, obtain definition evidence for that software before editing. Use the MS45 family page for the address-range and padding explanation.
Common calibration material
Continue with fuel mass and injectors and intake model, torque and DISA. Keep a worked result on this variant page with its exact software, hardware and measured behaviour.
Sources and scope
Original reference notes by Tuning Wiki, informed by the linked MS4X Wiki pages. MS4X Wiki contributors and the authors credited by each linked project remain the source authors. Sources checked 10 November 2026. Suggested validation steps and worked arithmetic are editorial guidance; they are not a tested calibration or a claim of hardware verification.
- Siemens MS45 (revision 23142).
- Definition Files (revision 23632).