Q: Q: Engine light on

asked by on

My Engine light is on due to an error code P0401.

Hi there. A code P0401 indicates that the EGR system is not working properly. The EGR, or exhaust gas recirculation system, is used for emissions to reduce the NOX emissions. If it’s not functioning and opening as it should, then this code will come up. Most of the time, the failure is due to a bad EGR valve or a failing EGR solenoid. I would typically use a computer scan tool to cycle the solenoid and see if it comes on. I could then see if the EGR valve is functioning by applying vacuum to it while the engine is running. This is best diagnosed with a computer scan tool. I would suggest getting some assistance from a certified mechanic from YourMechanic to make the repairs.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Q: Engine light on

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Lost power while driving. Wont crank. Check engine light is on.

Hello, thank you for writing in. There are several systems that may be malfunctioning. You should narrow in on the charging system first. Have your battery and your alternator checked. This can be done at home or at your local...

Q: Q: Problem with convertible top.

The electric convertible top on your vehicle may not be working for a number of reasons. The switch, wiring, or motor(s) that operate your convertible top could be faulty. I would recommend having an electrical systems check performed by a...

Q: Engine code P0401

Engine code P0401 on your Honda Accord indicates that there is low flow to the EGR valve. The repair for this is to remove the EGR valve and, using a special tool, cleaning the passages of the EGR tube. In...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.