hey im having problems with my ford f150 the code reads p0401 which is insufficient egr flow ... any ideas on how to fix that? i replaced egr valve and cleaned the throttle body neither helped ... thanks in advance

 

Might have a clog at the manifold.

 

thank you ill check it out

 

Another thing about the "insuficent egr flow" is vacuum hoses. you might have a vacuum hose that is dry rotted and is letting air in or out through the side of the hose. One good thing to do is to feel the vacuum hoses to see if they are really hard, which they shouldnt be, and if alot of black crap comes off the hose when you feel it.(like running your hand across the hose) That code explanation pretty much means that something is disturbing the flow or vacuum (pressure) inside those lines. You could have a clog like the guy previously said, or a vacuum hose could simply not be able to hold pressure due to deteriation of a hose.

 

Could be your gas cap as well.

 

gas cap? when i pump gas it leaks out of the filler hose sometimes could that be it?... and thanks for all the replies !

 

If your gas cap does not seal where the system can pull a vacuum on the tank you will get that code. My wife the cap off her car and got that code almost immediately.

 

DPFE sensor is usually at fault. Takes more time to find the $60.00 part than it does to change it. Just for the record, year and engine, and miles?

 

97 ford f150 166000 and yeah im taking the throttle body off tonight to clean ... if that doesnt help then im gonna check the fuel lines and then last step is the dpfe

 

and its the 4.6l