p1401- egr valve or DPFE sensor

[EMG7895]

I recently got a steady p1401 code, it came on and hasnt gone away. What is the most likely problem the valve or the sensor itself? It does have 200k miles on it and is the old metal version, not sure on the egr's history because i dont have all the paperwork with me now. I also recently had it all apart to change the valve cover gaskets and it all looked clean, no blockages. A search of the code revealed little so has anyone else experienced this?

 

[magngineer]

The sensor is most likely the culprit. I'm on my 3rd sensor on my 98 5.0L. The silicone rubber vacuum lines going to the sensor could also be bad.

If you have access to a hand vacuum pump you can check the EGR passage quite easily. Disconnect and plug the vacuum line going to the EGR valve. Connect the vacuum pump to the EGR valve. Start the car and let it idle. Apply vacuum with the hand pump to the EGR valve. The engine should stumble or stall if the passage is open. If it doesn't the passage is clogged or the diaphram in the EGR valve is bad. If the passage is open it's most likely the DPFE sensor.

One other thing that can cause that code to set is a bad vacuum solenoid that turns the EGR valve on and off.

Hope this helps.

 

[EMG7895]

this is a 4.0 ohv, ill test the vacuum though and see what the results are.