Exhaust Gas Recirculation Circuit Malfunction


Table of contents

P0403 PONTIAC Possible Causes

  • EGR volume control valve stuck open or closed
  • Faulty EGR volume control solenoid valve
  • EGR volume control solenoid valve harness is open or shorted
  • EGR volume control solenoid valve circuit poor electrical connection
  • EGR temperature sensor and circuit

How do I fix code P0403 PONTIAC?

  Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.

Cost of diagnosing the P0403 PONTIAC code

  The cost of diagnosing the P0403 PONTIAC code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

When is the code detected

  An improper voltage signal is sent to Powertrain Control Module (PCM) through the valve

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Possible engine hesitation

P0403 PONTIAC Description

  An Exhaust Gas Recirculation (EGR) system is used in order to lower Oxides of Nitrogen (NOx) emission levels. The EGR system accomplishes this by feeding small amounts of exhaust gas back into the combustion chamber. High combustion temperatures cause NOx. Combustion temperatures are reduced when the air/fuel mixture is diluted with the exhaust gases.
The EGR valve is designed to accurately supply exhaust gases to the engine without the use of intake manifold vacuum. The EGR valve controls the exhaust flow into the intake manifold from the exhaust manifold through an orifice with a Powertrain Control Module (PCM) controlled pintle. The PCM controls the pintle position using inputs from the Throttle Position (TP) sensor, the Manifold Absolute Pressure (MAP) sensor and, the Engine Coolant Temperature sensor. The PCM commands the EGR valve in order to supply the correct amount of exhaust gas recirculation for the current engine operating conditions.

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