I recently put on a JLP Ram Air kit and did the 'boost bypass' modification. Truck ran fine when I test drove it. Ran fine all day yesterday. Ran fine to work and to lunch today. Then I went to go run an errand and the Service Engine Soon light came on - truck still ran fine...even at WOT. Took it to Autozone....P0402...Excessive EGR Flow.

Should I check my vacuum lines on my boost bypass modification that I did? Maybe put some water on the connects and see if it gets blow off?

If everything looks normal, 'undo' the boost bypass mod, unplug the battery for 10 minutes and see if it comes on?

Am I on the correct path to diagnosing this code ?

Maybe this is what was causing my low rpm stumble as mentioned in another thread?



Or should I be looking for something totally different?

 

It seems that every time that I did a mod, oil separator, boost by pass, it has always been a vacuum line leak, related to something I did…. Check and recheck those lines, some have taken me a week to find, once the pvc plug was half in and half out, man that was a mother to find. Check and recheck those hoses…

 

A couple things could cause that code.

The EGR valve sticking open, which definetely would cause a low rpm stumble.

A vaccum leak or line problem would do the same thing.

Or the DPFE sensor. Ford has had alot of trouble with these, mainly on the Focus. I kept getting that EGR code on her and the car just ran really funny, even after I reset the code. It would come on and go off again. Then I noticed we were getting real crappy gas milage.


Cked the lines. Pulled the EGR and cleaned and checked it. Still doing it. Did a search and found it it was a HUGE problem. Called my dealer and they had 100 of them in stock.

This is what controls the EGR valve I guess. There should be a hose that comes off the egr tube that connects to this little black plastic thing. I think the one for the focus was like 30 bucks.

Check your lines, pull the EGR valve off and see if it's sticking (just suck on the vacuum fitting and see if the diaphram moves ok. If so, fill the valve with water and see if it leaks. If it does, junk the valve. If these two things check ok ok, and you still get the code, I'd go for the new sensor. Cheap enough. Could all just be coincedence that the problem is now after you touched the lines, or it could be directly related. Good luck.

 

If you need any egr stuff let me know.. i have all the stuff off my L.. It all worked perfectly fine

sidriver2k@yahoo.com

 

PoorSVTMan....

I might take you up on that. I was looking for some spare EGR hardware so i can powdercoat it. I will let you know.


As for the issue I originally posted about....I checked all of my vacuum lines and everything was tight. I am going to tape them up this evening just to be sure. I disconnected the negative battery cable for about 10-15 minutes. It erased the code. No code for my 25 minute drive to work today either. We will see how long it lasts.

 

if it's the DPFE Sensor, I haven't read of them just plain going bad so the code comes on right away. It never did that on my focus. It would kinda not work...........then work...........then not work. That's when the codes would come on and you could feel the car stumbling.

 

It sounds to me like you hooked the boost bypass up wrong, and now you are giving the wrong vacuum signal to the EGR. I've seen other people do the same thing. Can you post some pics of the related area?

 

I will see if I can post a pic up tonight of the boost bypass.

Although, I dont know how it could be hooked up wrong. I went right by the directions at RPM Outlet.com

 

This is what your should look like. You unplug the pink line and plug the boot where it came out of. You install a T fitting between the connection that goes to the stock boost guage. Then you connect the pink line there.

 

Oh jesus, that could be the problem there!!!!!

 

Thats exactly what mine looks like. No doubt about it. No stumbling either when the light was on. Although, I didnt really have a chance to go WOT for too long and test it out....not many places you can do that!

 

rpmoutlet tells you do to it the same way as you did yours...

http://rpmoutlet.com/boost%20bypass.htm

easier way is just to unplug the darn electrical conector and your done

 

You know I had the same code and it turned out that one of the lines on the (DPFE Sensor) had come loose. This sensor is in front (towards the front of the vehicle) ((almost below the throttle spring) and lower than the EGR valve. It has two lines coming out of it. I reinstalled the smaller of the two lines and then “T” wrapped them to keep them in. I also melted the vacuum line that comes out of the EGR valve it landed on that hot tube..

 

Well,

I cleared the code about two weeks ago by disconnecting the negative battery terminal. I checked all my wires and vacuum hoses, everything was fine. I have since put over 350 miles on the truck and the light has not come back on. It was tested for emissions yesterday and everything was fine. Musta just been 'one of those things'