I'm getting a PO401 OBDII code with a check engine light. EGR flow insufficient.
Anybody want ot guess if it's a stuck valve or clogged tubes?

Bill

 

The most common reason for this code is a bad DPFE sensor...

 

Really. Where is the DPFE sensor? Is this the sensor with the two hoses comng from the EGR tube?

 

Yes, it's rectangular shaped, 2 rubber lines coming out of the bottom, and a 3-wire electrical plug on it. You didn't say what engine you have, but on a 3.0L, it's mounted on the upper intake....

 

Sorry. 2000 3.0 flex fuel.

I found it between my two replies. Blew some carb cleaner through the tubes on the sensor and got some crud, including what looked like a hairball, to come back out at me.

I had to replace one of the rubber tubes a while back due to a hole and suspect that hair got sucked via the hole.

BTW, which one of rubber hoses goes where on the EGR tube?

Thanks
Bill

 

The hoses are different sizes (diameter) so you can probably figure it out that way.

Here is a summary of the Ford EGR/DPFE system that might help:

Ford DPFE/EGR System Summary

 

They may have been. But I replaced them with hoses of the same diameter.

Your diagram helps greatly.

Thanks, to you and Bob

 

As it turns out I had the hoses reversed. Maybe it will run a little better now.

Thanks again,
Bill

 

Well, I cleaned everything, made sure the hoses were correct and the code came back. Replaced the DPFE and still got the code. Replaced the EGR valve and have not gotten any CEL...yet.

But, now I experience hesitation and stumbling on acceleration. When cruising with the throttle just cracked open the truck "bucks". Sounds like bad EGR valve. Any ideas?

Thanks
Bill

 

Try resetting the PCM.....You can do this by disconnecting the negative battery cable, and short it to the positive battery terminal for a few seconds.

Good luck!!!!

 

Wow, never heard that before. So you're basically discharging all of the circuitry. Hmmm.

Thanks!

 

Yes, you hear of disconnecting the negative cable and waiting 10-15 minutes, and that is due to the time for the PCM internal filter capacitors to discharge. If you short the negative cable back to the positive terminal, the capacitors are discharged immediately.

 

I just did the deed and will see what happens tomorrow.

Thanks
Bill

 

I've always been told if you reset the PCM and restart the engine while warm, the PCM will use the warm engine settings as a base line. Any truth to that?

 

I do not think this is the case.....