I have done the search on this and there are many threads. My check engine light came on about 3-4 weeks ago and I finally got to check it yesterday. I threw the code P0401. I reset it to see if it would throw it again and it did today. I have read the threads about checking lines and cleaning the throttle body and doing the vacuum test and I will try to tackle that this weekend, but I haven't noticed any change in the vibration or idleing in my truck. My truck runs good and I haven't noticed a change since it threw this code. Is there always a big difference in the way it runs if it throws this code? I have a 02 4.6L with 89,000 miles.

I guess my question is should I just check all the possible solutions and see if the code goes off and if not it is the DPFE sensor?

I know there are many threads about this, so thank you for your replies!!
They are greatly appreciated.

 

The 0401 code (and the condition associated with it) won't necessarily cause idle problems because the EGR system is normally closed during idle. I'd start with the vacuum test since it'll give you an indication of the condition of the passages inside the intake elbow. If the engine stumbles and tries to die when you apply vacuum to the EGR valve the passages are probably OK.
Even then, I'd recommend cleaning them if you're replacing the DPFE sensor. It's about the cheapest thing you can do to your truck; a couple of buchs for some TB cleaner, maybe $15 dollars worth of gaskets, and a little elbow grease is all it takes.
It won't turn your truck into a missile, but at least the annoying light will go away.

 

This won't hurt my engine before I get it fixed, will it?

 

I've never heard of anybody having engine damage from it. Its just that annoying check engine light......

 

Nope

Your EGR valve is fine - That's usually a PO402 (poppet valve failure)

Plenum ports

Ruptured DPFE hoses

EGR pipe leak

But most likely a bad DPFE sensor. Replace with dealer part ONLY.

 

Thanks, I'm gonna check everything out this weekend hopefully!

 

The check engine light comes on when the operating temp is reached. I can reset the code 0401. It will then stay off until about the same time the next day. Some time the light will come on in the morning other times at night. But no matter what it is always at the same distance after I start moving. I have changed the EGR valve. But the problem is still there.grice97761@aol.com

 

I was thinking a p0401 could also be due to the ports in the intake plenum could be clogged. ( typical on the 4.6 engines ).



Larry.

 

Yea, what's up with that ?

 

I guess they are still trying to get everything moved around. The forum was not available yesterday and I saw a post the they were working on the Photo Galleries. Its kind of a bitch that there are links to all those photos in many of the forum threads.

 

Damn, I did finally get to my Galleries. I tried a few things and finally got it to go. Accidentally closed all my tabs - Now I can't remember how I got it to work. Mannnnn.

EDIT - Start at the Home Page logged out. Click Photo Galleries/log in/enter - your there.

 

Lucky you, it did not work for me.

 

Yea , I can get to yours that way as well.

This stuff looks like it would quench your thirst -



Yea , they will get them fixed soon. By the way , I think you were one of the first guys to help me fix my truck when I first joined. I know I was reading your posts before I was a member. Some things you don't forget. -

When you posted that Information about the - "Harness to close to the AC ACUMMULATOR can cause the motor to misfire" It was you and I think user "PKRWD" (spelling ?) that helped me with that one. Pulled the harness away while she was running and it cleared it up that quick.

That was awhile ago..

 

I remember you jbrew.

I also had to pull the harness away from my accumulator when I finally got the obdii code.

I still can't see any photo galleries. I get a screen that would allowed me to add a new album though.

I wonder if they got the photo galleries fixed and I got left out.

I guess I will have to start all over and use pictures of my mower instead and let the members translate it to F150 terms.

It took me 3 frikin days to get the flywheel off.



I used heat and vibration and PB blaster on it for 3 days.

I had to go to grade 8 bolts on the flywheel puller to keep this from happening...



Those shiny spots around the bolt holes are from the stress in the cast iron from the flywheel puller.

I was beginning to think it was welded on.



Larry

 

Yea , they get locked on the crank pretty good in time - get her wet once,- shortly after, the Kung Fu grip is applied. - I can tell by looking at the Armature, it's been awhile. - I know that just cleaning things up a bit helps. The electromagnets will thank you taking everything right to the wire wheel -

You can still use the Flywheel if you tweaked/stressed it a bit as long as it's still balenced and without fractures, I found applying pressure w/puller and using a brass hammer around the flywheel at the same time helps with removel.

A thin coating of Teflon grease works best for me on the crank/key/keyway.

What does this have to do with f150's. Well , everything with an engine on it at the house has been in the back of mine at one time or another,