Q: Egr and evap codes 455 & 405

asked by on August 23, 2016

Car hesitates on acceleration sometimes and surges on highway sometimes not all the time. I replaced egr valve cleared codes and two days late there back. I came to a stop once and the car stalled. I even replaced the fuel cap. How do I pin point the problem without spending a fortune replacing parts? Could it be purge valve or vent solenoid?

My car has 103000 miles.
My car has an automatic transmission.

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The trouble code P0405 is for the EGR sensor. This code indicates that the sensor is not giving correct voltage readings. You’ll need to replace the sensor and the sensor hoses. The hoses can clog or burn through which causes EGR malfunction.

Trouble code P0455 is for a leak in the purge vapor system and is for a major leak. This is caused by a leaking gas cap or a leaking purge valve in the engine compartment. Test the system using a smoke machine or run the engine and see if the purge valve leaks vacuum during idle. You can check this by disconnecting the vapor line that goes to the valve from the tank to see if it leaks. Afterwards, replace these components and clear the codes.

If you need some help with this, consider YourMechanic, as a certified technician can help diagnose your trouble codes firsthand and help you get your car running normally again.

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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