Injector rail pressure below spec
Real reading, clearly low. The stage before a derate or shutdown.
SPN 157 — Injector rail pressure below spec
SPN 157 is the parameter the ECM is flagging on Volvo, CAT, Detroit, International, PACCAR, MERCEDES, Mack, Cummins engines. The FMI that comes with it tells you how it failed. Each failure mode below has its own causes and its own test order — do not treat them as the same repair.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
Injector metering rail 1 pressure below normal - moderately severe
Real reading, clearly low. The stage before a derate or shutdown.
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