Dtc P01404

My 2001 Grand Prix's check engine light came on the other day and produced a P01404 trouble code. I know this is EGR stuck open code and changed the EGR valve. The check engine light still comes on and I still get the P01404 code. What else can it be. Is it possible to get a bad EGR valve. This valve has a solenoid instead of a vacuum diaphram otherwise it would be easy to test. Any helpp would be appreciated. Also, the check engine light usually comes on when engine is at idle and the engine also sometimes runs rough when this happens just as expected when EGR valve is open at idle.

There is a possibility that the reading from the EGR valve, coming from the sensor, is telling the computer that the valve is open, whether is is or not. If the problem, for example, is the result of the voltage to the sensor being missing, the resulting low reading could be due to the computer having its own issues. This is a good example of jumping to conclusions leading to erroneous parts changing. I have seen the problem simply being the result of incorrect programming and a reflash fixed the problem. Ray

Reset the PCM and see if that helps. Also check your gas cap is closed all the way.

Just disconnect the battery for an hour or so and see if the SES comes back on

I disconnected the negative terminal for an hour or so and that seems to have taken care of it. Thanks!