CEL wont go away (P0401)

Well ive been fighting with a CEL that goes away and comes back all the time. Sometimes when i reset the comp it will go away for about a week then it comes back on till i reset it again. Or the odd time it will just go away itself, but that doesnt happen anymore. Im curious because i bought a new EGR valve hopeing it would fix this problem, but it hasnt. Is there something else it could be? Im getting tired of seeing the CEL on the car. I heard someone say that i need to clean the egr passages, but im not sure what passages they mean. Just a few days ago i did the UIM and LIM intake cleaning thing with the vaccuum lines but the light is still on. Please help

remove the tb and you will see the passages. when those get clogged up you get a P0401

has nothing to do with the egr valve

Try what Brapple said and if it still doesn't go away, change the DPFE sensor....I had the same issue until I changed BOTH!

cnsidering it goes on and off periodicaly even though it sounds stupid i would just make sure u have a good sensor and a good connection to the sensor. ive known guys who have done a ton of work a car just to find out if they had made sure the sensor and wiring was clipped together completely they would have saved them selves alot of time

Where do i find this sensor? I took the throttle body off last year when i got the car and cleaned in there and i though i got most of the crap out of there. But ya maybe ill take a look at the DPFE sensor and maybe just replace it. But im not sure what im looking for. If anyone has a pic where they can circle it that would be great.

Yeah I had to do the EGR passage cleaning. give me a few minutes and I'll fine the pictures. There are somewhere on my site.

This is the view down the TB

This is what is behind the TB and The TB gasket.

You'll need to take off your intake, the TB, and the TB gasket. You'll also need a pick set, a new TB gasket, and a gun barrel cleaner(???) probably wrong name for it. They look like a copper pipe cleaner. I think it took me around an 1-2 hours. Mainly because I had no clue what I was doing. lol And I really hadn't done anything else to my car at that point.

The DPFE sensor is 'under' the EGR valve. It has (IIRC) two rubber hoses going to the bottom of it and 2 or 4 screws (can't remember) mounting it toe the UIM (IIRC).

And a quick Yahoo Images search with "DPFE"..