P0487 – Exhaust Gas Recirculation Throttle Control Circuit A Open

What is Code P0487?

P0487 is an OBD-II generic powertrain code that stands for "Exhaust Gas Recirculation (EGR) Throttle Control Circuit 'A' Open". This code indicates there is an electrical issue with the EGR throttle control valve circuit.

How Serious is Code P0487? Can You Keep Driving?

Code P0487 is considered a critical issue that can lead to engine damage if not addressed. While the vehicle may still be drivable in the short term, it's recommended to diagnose and fix this problem as soon as possible to prevent further issues. Continuing to drive with the Check Engine Light on due to P0487 can cause reduced fuel economy, hesitation, and rough running.

Technical Details

The EGR system redirects a portion of the exhaust gases back into the intake to lower combustion temperatures and reduce NOx emissions. The EGR throttle control valve regulates the amount of exhaust gas flow.

Code P0487 is set when the powertrain control module (PCM) detects an open circuit condition in the wiring for the EGR throttle control valve. The PCM monitors the voltage signals from this valve to determine if they are within the expected range based on its control inputs.

This is a generic powertrain code that applies to all makes and models of vehicles (1996-newer) equipped with OBD-II, though the specific repair steps may vary slightly between manufacturers.

Common Causes

Some of the most common causes of code P0487 include:

• Damaged or open circuited wiring/connectors in the EGR throttle control valve harness
• Faulty EGR throttle control valve
• Clogged or stuck open EGR valve
• Issues with the PCM (rare)

Diagnosis Steps

1. Connect an OBD-II scanner and check for any other codes. Address those first if present.
2. Visually inspect the wiring and connectors going to the EGR throttle control valve. Look for damaged, burnt, corroded, or disconnected wires.
3. Using a multimeter, check for reference voltage and ground signals at the EGR valve connector.
4. Disconnect the valve and test its resistance. Compare to specifications.
5. If the wiring and valve test okay, the issue is likely with the PCM.

Repair Solutions

• Repair damaged wiring/connectors for the EGR throttle control valve
• Clean the EGR valve and passages if clogged
• Replace a faulty EGR throttle control valve (~$200-400 part)
• Reflash or replace the PCM if it is defective

Prevention

Proper maintenance of the EGR system can help prevent P0487 from occurring. This includes:

• Regularly inspecting and cleaning the EGR valve every 50,000 miles (80,000 km)
• Addressing any EGR related codes promptly
• Avoiding aftermarket air filters that allow debris into the intake

Repair costs for code P0487 typically range from $100-600 depending on the root cause, with PCM replacement being the most expensive fix. The EGR valve itself costs around $200-400 on average.

Other codes that may appear along with P0487 include P0405 (EGR Position Sensor A Circuit Low), P0406 (EGR Position Sensor A Circuit High), and other EGR system related faults.

In summary, code P0487 is a critical issue with the EGR throttle control valve circuit that requires prompt diagnosis and repair to avoid drivability issues and potential engine damage. Proper inspection and regular maintenance of the EGR system is key to preventing this fault from occurring.

Frequently Asked Questions About P0472

What does code P0487 mean?

P0487 stands for “Exhaust Gas Recirculation (EGR) Throttle Control Circuit ‘A’ Open”. It indicates an electrical issue with the EGR throttle control valve circuit.

How serious is the P0487 code?

P0487 is considered a critical issue that can lead to engine damage if not addressed promptly. While the vehicle may still be drivable, it’s recommended to diagnose and fix the problem as soon as possible.

Can I continue driving with code P0487?

While you may be able to drive short distances, it’s not recommended to continue driving with this code active. Doing so can cause reduced fuel economy, hesitation, and potential engine damage.

What are the common symptoms of P0487?

Common symptoms include illuminated Check Engine Light, reduced fuel economy, engine hesitation, and rougher than usual engine operation.

What causes the P0487 code to appear?

Common causes include damaged wiring/connectors in the EGR throttle control valve harness, a faulty EGR throttle control valve, clogged or stuck open EGR valve, and rarely, issues with the Powertrain Control Module (PCM).

How is P0487 diagnosed?

Diagnosis typically involves scanning for codes, visual inspection of wiring and connectors, testing the EGR throttle control valve circuit with a multimeter, and checking the EGR valve operation.

What parts are involved with code P0487?

The main components involved are the EGR throttle control valve, its wiring harness, connectors, and the PCM.

Is P0487 a generic or manufacturer-specific code?

P0487 is a generic powertrain code that applies to all makes and models of vehicles equipped with OBD-II (1996 and newer).

How do I fix code P0487?

Common fixes include repairing damaged wiring/connectors, cleaning a clogged EGR valve, replacing a faulty EGR throttle control valve, or in rare cases, reflashing or replacing the PCM.

What is the cost to repair P0487?

Repair costs typically range from $100-600 depending on the root cause. The EGR valve itself costs around $200-400 on average.

Can I repair P0487 myself or do I need a professional?

While some basic diagnostic steps can be performed by DIY enthusiasts, professional diagnosis and repair are recommended due to the complexity of the EGR system.

How can I prevent P0487 from occurring?

Regular maintenance of the EGR system, including inspecting and cleaning the EGR valve every 50,000 miles, can help prevent this issue.

Are there any other codes commonly associated with P0487?

Yes, P0405 (EGR Sensor A Circuit Low) and P0406 (EGR Sensor A Circuit High) are often seen alongside P0487.

Will P0487 clear itself?

While the code may clear itself temporarily, it will likely return if the underlying issue isn’t addressed.

Can a bad battery cause P0487?

While unlikely, a weak battery could potentially cause erratic electrical behavior that might trigger this code.

Does P0487 affect emissions testing?

Yes, this code will likely cause a vehicle to fail an emissions test.

Is there a difference in P0487 between gasoline and diesel engines?

While the code definition is the same, the specific components and repair procedures may differ between gasoline and diesel engines.

Can weather conditions trigger P0487?

Extreme weather conditions could potentially exacerbate existing issues with the EGR system, but are unlikely to be the sole cause of this code.

How long does it typically take to repair P0487?

Repair time can vary from 1-3 hours depending on the specific cause and required fix.

Will P0487 cause my vehicle to fail inspection?

Yes, in most regions, an active P0487 code will cause a vehicle to fail inspection due to its impact on emissions control systems.