P243B: Bank2 GPF restriction monitoring needs warm, sustained exhaust flow

P243B is Ford’s bank 2 gasoline particulate-filter restriction classification associated with forced limited power. It is listed in the high-soot-loading test, separate from the deteriorated or missing-substrate monitor. The classification therefore must not be treated as interchangeable with a low-backpressure missing-filter result.

The operating window is deliberately restricted

The source requires exhaust flow between 400 and 850 m³/h and a filter temperature above 250°C for 30 seconds. Its stated monitoring duration is five seconds after entry conditions are satisfied. An unheated, low-flow pressure reading does not reproduce this functional opportunity.

The monitor also depends on the listed pressure, temperature, airflow and related systems being healthy. A result should not be interpreted as though those supporting measurements were verified merely because a code is present.

Keep a threshold-label problem explicit

The restriction paragraph describes a normalized-pressure ratio above 1.0 but repeats the phrase “missing brick threshold” used in the separate missing-substrate check. That labeling ambiguity is not silently converted here into a universal restriction pressure or a complete calibration formula.

Preserve bank 2 identity, eligible flow and temperature, pressure information and the reported power-limiting classification. The source does not justify filter removal, forced regeneration or a replacement decision from this code alone. The applicable vehicle procedure must establish what produced the restriction assessment.

Source and applicability

Ford 2024–2025 gasoline OBD summary, July 16, 2024 revision; only the described monitor and architecture. Model, engine and calibration fitment are not inferred. The monitor explanation does not identify a failed part or replace the applicable service procedure. Ford PDF, page 5.