Ford F150 1999 code P0401 egr flow insuff.

Hi all!

I have a Ford F150 1999 with a check engine light ON. I got the code P0401...Egr flow insuff. With the help of you in this forum, I've changed DPFE sensor( including its hoses); egr valve and clean its ports; valcunn valve. Unfortunity, the code keeps coming back. The truck is due to have inspection or will be fined $250.00 by the DMV...i've read some posts in this forum mentioning about valcunn leak. How do I check for valcunn leak? Engine is running fine. Please HELP HELP HELP.

I have the same problem with my Taurus, changing the dpfe fixed it for a few days but the fault code came back. I had enough of trying to fix it myself to a took it in to my local dealership, they said it was a intake gasket leak that was causing the code. Since they wanted $800+ beans to fix only that I passed, when I get around to it.

Anyway, how long does it take after clearing the code for it to come back on?
Mine took several days (few hrs worth of driving) to light back up, my advice would be to clear it just before you head to the DMV, this way it'll pass inspection and buy you some time to fix it.

Gdluck!