P0487 OBD-II Trouble Code: Exhaust Gas Recirculation Throttle Control Circuit A

P0487 code definition

The P0487 code indicates that there has been a malfunction in the exhaust gas recirculation (EGR) system. This code may also be present in conjunction with P0409.

What the P0487 code means

The P0487 code means that the car’s computer did not register the correct amount of air pressure in the manifold when the EGR valve opened. Depending on the make and model in question, the vehicle may use an EGR position sensor, or it may measure manifold air pressure and exhaust feedback to ensure the right amount of air pressure is present.

What causes the P0487 code?

The P0487 code can be caused by a number of things that are common across virtually all vehicles. These include the following:

  • Clogged or blocked passages within the EGR valve
  • Failure of the EGR valve
  • Faulty MAP sensor
  • Failed EGR control solenoid
  • Damaged or broken vacuum line
  • Blocked DPFE sensor passages (with Fords, predominantly)

What are the symptoms of the P0487 code?

There are very few symptoms associated with the P0487 code, other than the Check Engine light illuminating. However, some drivers may notice reduced fuel economy, hesitation under acceleration and rougher than usual engine operation.

How does a mechanic diagnose the P0487 code?

The first step to diagnose the P0487 code is to connect a handheld OBD II scanner to the car’s computer and read the code(s) stored there. Next, the mechanic should test drive the vehicle to see if the code resets.

Next, the mechanic should conduct a visual inspection of all the vacuum lines in the EGR system. Note that damaged vacuum lines are actually the most common cause of the P0487 code, not a failed or blocked EGR valve. After inspecting the vacuum lines, the wiring and all connections should also be inspected and repaired or replaced if necessary.

If there is sufficient vacuum for the system, the EGR valve should be inspected. Some units contain the solenoid itself, while it is separate on other vehicles. The solenoid should be diagnosed, followed an inspection to determine if the EGR valve itself is clogged or blocked. Note that if the EGR valve is electronic, rather than vacuum-operated, the mechanic will need to use a scanner to operate the EGR for testing while the engine idles.

If the EGR valve is in good working condition, then the problem may lie within the EGR passages in the throttle body.

Common mistakes when diagnosing the P0487 code

The single most common mistake when diagnosing the P0487 code is immediately assuming that the problem is the EGR valve. While failure of the valve itself is not uncommon, it’s actually more common for the issue to lie with a damaged vacuum line, or with a faulty solenoid. Not only will replacing the valve not solve the problem, but these parts are actually more expensive than many other fixes.

How serious is the P0487 code?

The P0487 code may not affect your ability to drive the car very much, but it can be an issue. It will also prevent your car from passing emissions testing and should be repaired as soon as possible.

What repairs can fix the P0487 code?

A number of possible repairs can be used to fix the P0487 code, including the following:

Additional comments for consideration regarding the P0487 code

Your car’s exhaust gas recirculation system is an important part of both the emissions system and your car’s fuel system. Exhaust gases must be re-burned in order to improve fuel economy while reducing the amount of vapor expelled into the atmosphere.

Need help with a P0487 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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