P0487
UniversalExhaust Gas Recirculation Throttle Position Control Circuit
Medium SeverityThis code indicates an electrical malfunction within the circuit that controls the position of the Exhaust Gas Recirculation (EGR) throttle. This issue can prevent the engine from accurately regulating intake airflow, potentially leading to performance problems or higher emissions.
⚠️ Before You Begin (Safety First)
Always ensure the vehicle is safely parked with the engine off and cool before beginning any inspection or repair. Disconnect the negative battery terminal to prevent accidental electrical shorts. Wear appropriate personal protective equipment, such as gloves and eye protection.
Common Symptoms
- Check Engine Light illuminated
- Rough idle
- Stalling
- Reduced engine performance
- Poor fuel economy
- Increased emissions
- Engine hesitation
Common Causes
- Faulty EGR throttle position sensor
- Wiring harness issues (chafed, broken, corroded)
- Poor electrical connection at the EGR throttle position sensor
- Faulty EGR throttle body assembly
- Powertrain Control Module (PCM) malfunction (rare)
Frequently reported on: 2007-2010 Ford F-250 (diesel), 2008-2012 Dodge Ram 2500 (diesel), 2009-2013 Chevrolet Silverado 2500HD (diesel), 2005-2008 Jeep Grand Cherokee (some diesel variants), 2006-2009 Mercedes-Benz E320 (CDI)
Diagnostic Steps
- Visually inspect the wiring harness and connectors leading to the EGR throttle position sensor/actuator for any signs of damage, corrosion, or loose connections.
- If accessible, clean the electrical connectors with an appropriate electrical contact cleaner.
- Using a multimeter, test the continuity and resistance of the EGR throttle position control circuit wiring if a wiring diagram is available.
- With a scan tool, monitor the EGR throttle position sensor readings to check for erratic or absent signals.
- Clear the code and test drive the vehicle to see if the code returns.
- If problems persist, replacement of the EGR throttle position sensor or the entire EGR throttle assembly may be necessary.
👨🔧 When to Call a Professional
If after performing a thorough visual inspection and basic circuit checks you are unable to identify the source of the problem, or if the repair requires specialized tools or advanced electrical diagnostics, it is highly recommended to consult a certified professional mechanic.
Commonly Asked Questions
What is the EGR throttle position control circuit?
It is the electrical pathway that monitors and controls the position of a secondary throttle valve, often used in conjunction with the EGR system to optimize exhaust gas flow and intake air for combustion efficiency and emissions reduction.
Can I drive with a P0487 code?
While your car might still be driveable, it is not recommended to ignore this code. It can lead to decreased fuel economy, increased emissions, and potentially more serious engine problems if not addressed promptly.
Is the EGR throttle the same as the main throttle body?
No, the EGR throttle is typically a smaller, secondary throttle valve used specifically to manage airflow related to the EGR system, distinct from the primary throttle body that controls overall engine air intake.
How can I test the EGR throttle position sensor?
You can test the sensor by checking its electrical resistance or voltage output with a multimeter while manually moving the throttle plate (if possible and safe to do so), comparing readings to factory specifications. A scan tool can also show live data from the sensor.
What is the most common fix for P0487?
The most common fix is usually inspecting and repairing damaged wiring or connectors, or replacing a faulty EGR throttle position sensor or the entire EGR throttle assembly if the sensor is integrated.