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Code 51 (Standard Emissions) - Exhaust Gas RECIRCULATION: Notes

Exhaust Gas Recirculation (EGR) Solenoid Vacuum (SV) valve is controlled by ECM. EGR SV valve is supplied with battery voltage through Fuel Injector (FI) relay. ECM completes ground circuit to energize EGR SV valve. Code 51 will set when system is operating in closed loop operation and MAP is less than a calibrated value.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Checks circuit for a short to ground.
  2. Checks for voltage from Fuel Injection (FI) relay.
  3. Checks circuit for a short to ground or a faulty ECM.
  4. Checks circuit for an open in Green wire.
  5. High resistance in EGR SV valve can set Code 51.