P0401 Exhaust Gas Recirculation Flow Insufficient Detected
07-07-2009, 01:32 PM
#2
2nd Gear Member
Join Date: Jun 2008
Location: Lexington, KY
Posts: 299
Chances are your DPFE sensor went bad; it's much more common than the EGR valve itself going bad.
If you want to check your DPFE sensor before replacing it (to make sure it's actually what's gone bad), here's a how-to on testing the sensor.
If you want to check your DPFE sensor before replacing it (to make sure it's actually what's gone bad), here's a how-to on testing the sensor.
07-07-2009, 05:27 PM
#3
4th Gear Member
Join Date: Nov 2007
Location:
Posts: 1,530
I've had this code on my old 95, I cleaned out the egr valve, problem solved. I wouldn't rule out the dpfe as mentioned, sometimes they get condensation build up, try blowing it out with compressed air, or just replace, there not expensive and there easier to get to on the new edges(in front not back).
07-08-2009, 03:18 PM
#4
3rd Gear Member
Thread Starter
Join Date: Aug 2007
Location: CA
Posts: 880
I'll try cleaning the DPFE sensor first. A lot of other threads point to this problem being associated with the code my car is throwing. As for using a air compressor to blow it out, do I want to use low pressure or does it matter? I don't want to mess up anything on the sensor. Is there a cleaner for it?
05-03-2010, 02:25 PM
#7
3rd Gear Member
Thread Starter
Join Date: Aug 2007
Location: CA
Posts: 880
So I'm bringing this thread back from the dead because my car started throwing the same code again, P0401.
I replaced the DPFE sensor months ago and it turned off the 'check engine' light.
Now the light is back on, should I try replacing the EGR?
I replaced the DPFE sensor months ago and it turned off the 'check engine' light.
Now the light is back on, should I try replacing the EGR?
05-07-2010, 05:08 PM
#10
Gentleman's Relish
Join Date: Feb 2005
Location: AZ
Posts: 13,090
That is not an option in Cali. He'll get an automatic fail when they hook up the OBDII computer to his car...
Did you actually clean the EGR valve or tubes before you replaced the DPFE sensor or did you just replace it and move on? If it keeps coming on after a few months you're probably getting carbon build up in the EGR tube that until it's cleaned out, will keep throwing the code. Being that you are in cali you will have a car with A.I.R. Tubes. These are aluminum tubes connected to the exhuast manifold on each side of the car. Each tube is connected facing the front of the car.
Pull them off and I bet you have a boat load of carbon build up on them. Clean them out and then that should get rid of your problem. I had a 2000 V6 and that was the problem I had.
Did you actually clean the EGR valve or tubes before you replaced the DPFE sensor or did you just replace it and move on? If it keeps coming on after a few months you're probably getting carbon build up in the EGR tube that until it's cleaned out, will keep throwing the code. Being that you are in cali you will have a car with A.I.R. Tubes. These are aluminum tubes connected to the exhuast manifold on each side of the car. Each tube is connected facing the front of the car.
Pull them off and I bet you have a boat load of carbon build up on them. Clean them out and then that should get rid of your problem. I had a 2000 V6 and that was the problem I had.
Last edited by Derf00; 05-07-2010 at 05:12 PM.