ok the problem i am having is the check engine light is coming on with a code of p0401 egr flow insufficient. has anyone ran into this problem before if so could you help me out ?

 

Welcome to the forum.
What are you working on?

 

it is a ford f150 xlt 4.6l triton. do you have any idea what it might be and have you ran into this problem before

 

It's usually one of two things. Either the EGR port in the intake is clogged or the DPFE sensor is bad. Most common is the sensor, but if the engine has alot of miles on it, you may check the EGR first. At an idle, apply direct vaccum to the EGR valve. The engine should stumble and even die. If not, the the ports are clogged. If it does bog or die, then the sensor is bad.

 

the auto zone place told me that that the egr valve could be defective and or the egr pressure sensor. how would i apply vacuum pressure to the egr valve to see if it is bad ? im kinda new at this thing so you might need to break it down barney style for me to understand sorry.also what is the dpfe sensor? they didnt say anything about that ?

 

That is the EGR sensor. It tells the PCM if there is EGR flow or not. It usually has 2 lines that are attatched to the EGR tube running up from the exhaust to the EGR valve.
You can hook up a vacuum hose to the EGR valve and suck on it really hard. That should be enough to open it to see if the idle changes. Or you can use a hand held vacuum pump which can be purchased at most auto parts stores. It works great for bleeding brakes by youself too.

 

ill let you know how things turn out thank you for your help

 

ok i did that sucking thing and the idle dropped like it was going to stall. now what does that mean is that good or bad?

 

that is good, it means the egr port in the intake isn't cloged and that your problem is most likly the egr sensor.




(sorry to steal your thunder LxMan1)

 

so is the egr sensor is that what they call the DPFE sensor? or is it just called the egr sensor?

 

I think DPFE sensor is the techinical term. When you got to the parts store i would call it the egr sensor. (alot of the guys behind the counter aren't exctly the brighest crayon in the box)

 

thanks for all your help ill be sure to post on here what the results are

 

not a problem glad to help

 

I believe that is exactly what just went on my F150. I was in FL @ the time and engine light stayed on. My original dealer checked it and advised me the sensor went and I got it replaced in GA when I got home. Mine went at 22K miles which is not normal. Usually they go around 60K I believe.

 

Actually, I pulled my work order and my code was P1406 which is different from yours. My part no. 3L3Z*9D475*DA which is the exhaust valve. They replaced my EGR valve and/or gasket. I hope that is helpful.