My 1998 F-150 with the 4.6L with 88K miles is throwing the P1401 Code. Before it was the P0401. That problem is fixed. The P1401 says I have High Circut Voltage to my DPFE Sensor. I replaced it, and the light is still on. I cleared the code at my auto shop class. Then the light came back on after 3 drive cycles.

Anyone have any suggestions on to which my problem is occuring?

-Alex

 

I would check the wiring harness and connector to the DPFE.

 

Have you tried replacing the EGR valve? I have a P1401 code also and have not had a chance to try a new EGR valve, but I have read other threads on the problem. It seems the P1401 code is triggered by improper DPFE circuit voltage which is caused by unacceptable vacuum from a faulty EGR valve.
Someone please correct me if I’m wrong.