P054F: idle injection quantity above the selected maximum map

P054F checks whether torque-forming injection quantity at idle is greater than 1.5 times the applicable maximum-fuel map value. The cited strategy selects different maps according to combustion mode and whether the transmission is in gear or park/neutral.

Context determines the comparison

Engine speed and coolant temperature are map inputs. Exhaust warm-up and hydrocarbon-unloading modes do not necessarily share the default idle threshold. A quantity that looks large without this context is insufficient evidence of the documented failure.

Gear must remain unchanged and the enabling conditions must hold continuously for more than four seconds. The filter uses 71 failed samples among 142, sampled once per cylinder firing event, with Type B, two-trip reporting.

Distinguish idle control from a direct leakage diagnosis

The continuation requires very low vehicle speed, effectively released accelerator input, a running engine, inactive power take-off and run/crank voltage of at least 11 V. It also checks relevant temperature, gear, speed, pedal and injection validity.

For verification, record the selected mode, gear and mapped comparison during an eligible idle interval. The code describes an excessive quantity relative to an expectation; it does not independently prove a leaking injector or excessive rail pressure. Any physical fuel-system diagnosis must follow the exact vehicle procedure rather than treating the 1.5 multiplier as a general repair specification.

Source and applicability

2025 GM 25OBDG04B diagnostic parameter tables; the cited monitor only. Vehicle, engine and calibration applicability must be confirmed separately. These tables describe detection logic, not a complete repair procedure or a component replacement verdict. gm-2025-04b, PDF page 1221; gm-2025-04b, PDF page 1222; gm-2025-04b, PDF page 1223.