P228DFuel Pressure Regulator A Exceeded Control Limits - Pressure Too High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P228D is the opposite of P228C: measured rail pressure stays above the setpoint for too long although regulator A should be cutting delivery. GM's gasoline table 25OBDG03A flags it when the high-pressure pump supplies more than requested for 10 of 12.5 s, as Type A; its 2018 diesel table uses minus 13 MPa with the metering unit in closed loop (Type B), and table 24OBDG07 minus 3 MPa for 7 s. Causes range from a pump control valve that will not shut off, via a pressure sensor reading wrong, to calibration: GM bulletin 17-NA-069 cures P228D on 5.3 L and 6.2 L V8s by reprogramming, and PACCAR bulletin E114 links it, with P0094, to defective unit pumps on MX-13 truck engines. Expect harsh running or derated power.
- What you may notice
- Check engine light
- Louder injection noise or rough idle
- Reduced power in some cases
- Likely causes
- LikelyPump control or metering valve not reducing delivery
- PossibleEngine control software needing an update
- PossibleRail pressure sensor reading too high
- RareDefective unit or high-pressure pump (truck engines)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €1,800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.