AI Diesel Tech
P0201OBD-IIINJECTOR

Injector Circuit Malfunction — Cylinder 1

Common Symptoms

  • Check Engine Light illuminated
  • Rough idle or engine misfire
  • Poor fuel economy
  • Engine lacks power or hesitates under acceleration
  • Strong fuel smell from exhaust
  • Engine may run on only some cylinders

Most Likely Root Causes

  • Faulty fuel injector on cylinder 1
  • Open or short circuit in injector wiring harness
  • Corroded or loose injector connector
  • Failed injector driver circuit in the PCM
  • Damaged wiring between PCM and injector

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Component Location

Cylinder 1 fuel injector is located in the fuel rail on the intake manifold at the number one cylinder position.

Manufacturer Notes

Some manufacturers use individual fuses or relays for injector circuits which should be inspected when diagnosing this code.

Also diagnosing J1939 SPN/FMI codes?

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