Powertrain, generic (extended)

P228A Fuel Pressure Regulator A - Forced Engine Shutdown

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P228A is a protective shutdown code: the engine computer has stopped the engine because rail pressure could not be held even with fuel pressure regulator A at full authority. In GM's 2018 diesel tables regulator 1 (A) is the fuel metering unit on the high-pressure pump; the fault is logged when actual pressure lags the setpoint by more than 40 MPa while the commanded pump flow is already at its maximum, in 640 of 800 samples taken every 12.5 ms (about 8 s), as a Type A code. GM bulletin 18-NA-103 lists P228A and P228B next to P0087 when gelled winter diesel starves the in-tank pump. P228B is the same reaction for regulator B, P228C the milder control-limit warning. Expect a stall or no restart until supply is restored.

Likely causes

Fuel supply starved (gelled or waxed diesel, clogged filter, failing in-tank pump)
Fuel metering unit on the high-pressure pump sticking or worn
High-pressure pump no longer reaching the required delivery
Leak in the high-pressure circuit or injector return

Symptoms

  • Engine stalls while driving or shuts off shortly after starting
  • Long cranking or no restart
  • Check engine light on, often with P0087
  • Whining in-tank fuel pump in cold weather

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–3,000
Time0.5–6 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel pressure regulator

Related codes

P228BP228CP0087P0089P229A

References: gsi.ext.gm.com, static.nhtsa.gov, law.cornell.edu.