CEL P0401 - DPFE Sensor?
isisfreak
08-12-2006, 04:45 PM
I have a 2002 Cougar Sport with about 60k miles on it. I've had a CEL on for about 3k now. It has a rough idle, has been sluggish, and I'm getting about 17mpg. I tried cleaning the EGR valve, nothing. So I replaced it, still nothing.
I've read that it could be the DPFE sensor, but I can't find it. I've read this how to ( http://www.newcougar.org/forums/showthread.php?t=2193&highlight=dpfe ), to replacing the DPFE, but I don't see it anywhere. Is it different in the 2002 year? Does the 2002 even have a DPFE?
I've also read that you can try cleaning and rebuilding the upper and lower intake manifolds ( http://www.contour.org/mods/mods.php?s=howto&displayid=17 ). I've heard that this could fix performance problems and CEL. But, it seems like a lot of work and money to do if it's not going to fix anything or make a difference. I don't really have spare cash right now. I also hear that it's easier to do plugs on the car with the UIM off, so I would do those if I ended up cleaning and rebuilding them, which is even more money. Kinda opening up a can of worms, eh?
Any suggestions? Right now I'm thinking that I'm going to replace the DPFE if I can find it. Also thinking that I'll clean the throttle body and see if that helps? I appreciate any help that anyone has to offer. I've been playing around with this stupid CEL for awhile now. Can't do any mods until this thing is atleast running good stock!
I've read that it could be the DPFE sensor, but I can't find it. I've read this how to ( http://www.newcougar.org/forums/showthread.php?t=2193&highlight=dpfe ), to replacing the DPFE, but I don't see it anywhere. Is it different in the 2002 year? Does the 2002 even have a DPFE?
I've also read that you can try cleaning and rebuilding the upper and lower intake manifolds ( http://www.contour.org/mods/mods.php?s=howto&displayid=17 ). I've heard that this could fix performance problems and CEL. But, it seems like a lot of work and money to do if it's not going to fix anything or make a difference. I don't really have spare cash right now. I also hear that it's easier to do plugs on the car with the UIM off, so I would do those if I ended up cleaning and rebuilding them, which is even more money. Kinda opening up a can of worms, eh?
Any suggestions? Right now I'm thinking that I'm going to replace the DPFE if I can find it. Also thinking that I'll clean the throttle body and see if that helps? I appreciate any help that anyone has to offer. I've been playing around with this stupid CEL for awhile now. Can't do any mods until this thing is atleast running good stock!
KimMG
08-12-2006, 11:45 PM
What exactly is the code causing the CEL to come on? Places like Autozone will read the codes for free.
isisfreak
08-13-2006, 10:50 AM
The code is P0401 EGR Flow Insufficient. It's the only code coming up.
reekor
08-13-2006, 11:47 AM
Talk to your local ford dealer, the DPFE sensor still might be covered under warranty. The ford/mazda DPFE sensors are factory junk and people are having nothing but problems with them. I know that ford did have a recall on the DPFE sensors, not sure what cars and what years, but this problem goes as far back as 1996 on some cars.
See this link
http://autos.msn.com/research/vip/Reliability.aspx?year=2002&make=Mercury&model=Cougar
I have a 2002 Cougar Sport with about 60k miles on it. I've had a CEL on for about 3k now. It has a rough idle, has been sluggish, and I'm getting about 17mpg. I tried cleaning the EGR valve, nothing. So I replaced it, still nothing.
I've read that it could be the DPFE sensor, but I can't find it. I've read this how to ( http://www.newcougar.org/forums/showthread.php?t=2193&highlight=dpfe ), to replacing the DPFE, but I don't see it anywhere. Is it different in the 2002 year? Does the 2002 even have a DPFE?
I've also read that you can try cleaning and rebuilding the upper and lower intake manifolds ( http://www.contour.org/mods/mods.php?s=howto&displayid=17 ). I've heard that this could fix performance problems and CEL. But, it seems like a lot of work and money to do if it's not going to fix anything or make a difference. I don't really have spare cash right now. I also hear that it's easier to do plugs on the car with the UIM off, so I would do those if I ended up cleaning and rebuilding them, which is even more money. Kinda opening up a can of worms, eh?
Any suggestions? Right now I'm thinking that I'm going to replace the DPFE if I can find it. Also thinking that I'll clean the throttle body and see if that helps? I appreciate any help that anyone has to offer. I've been playing around with this stupid CEL for awhile now. Can't do any mods until this thing is atleast running good stock!
See this link
http://autos.msn.com/research/vip/Reliability.aspx?year=2002&make=Mercury&model=Cougar
I have a 2002 Cougar Sport with about 60k miles on it. I've had a CEL on for about 3k now. It has a rough idle, has been sluggish, and I'm getting about 17mpg. I tried cleaning the EGR valve, nothing. So I replaced it, still nothing.
I've read that it could be the DPFE sensor, but I can't find it. I've read this how to ( http://www.newcougar.org/forums/showthread.php?t=2193&highlight=dpfe ), to replacing the DPFE, but I don't see it anywhere. Is it different in the 2002 year? Does the 2002 even have a DPFE?
I've also read that you can try cleaning and rebuilding the upper and lower intake manifolds ( http://www.contour.org/mods/mods.php?s=howto&displayid=17 ). I've heard that this could fix performance problems and CEL. But, it seems like a lot of work and money to do if it's not going to fix anything or make a difference. I don't really have spare cash right now. I also hear that it's easier to do plugs on the car with the UIM off, so I would do those if I ended up cleaning and rebuilding them, which is even more money. Kinda opening up a can of worms, eh?
Any suggestions? Right now I'm thinking that I'm going to replace the DPFE if I can find it. Also thinking that I'll clean the throttle body and see if that helps? I appreciate any help that anyone has to offer. I've been playing around with this stupid CEL for awhile now. Can't do any mods until this thing is atleast running good stock!
reekor
08-13-2006, 11:50 AM
P0401 OBD-II Trouble Code
Technical Description
Insufficient EGR Flow
What does that mean?
EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR.
Symptoms
You may notice drivability problems such as pinging (a.k.a. pre-ignition knock) when the engine is under load or the vehicle is at higher speeds. There may also be other symptoms.
Causes
A code P0401 most likely means one or more of the following has happened:
* The DPF (differential pressure) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (most likely carbon buildup)
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum
Possible Solutions
In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.
* Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's. There should be a noticable difference in RPM's with the EGR open
* Clean out the EGR valve to remove deposits
* Replace the DPF sensor
* Replace the EGR valve
I have a 2002 Cougar Sport with about 60k miles on it. I've had a CEL on for about 3k now. It has a rough idle, has been sluggish, and I'm getting about 17mpg. I tried cleaning the EGR valve, nothing. So I replaced it, still nothing.
I've read that it could be the DPFE sensor, but I can't find it. I've read this how to ( http://www.newcougar.org/forums/showthread.php?t=2193&highlight=dpfe ), to replacing the DPFE, but I don't see it anywhere. Is it different in the 2002 year? Does the 2002 even have a DPFE?
I've also read that you can try cleaning and rebuilding the upper and lower intake manifolds ( http://www.contour.org/mods/mods.php?s=howto&displayid=17 ). I've heard that this could fix performance problems and CEL. But, it seems like a lot of work and money to do if it's not going to fix anything or make a difference. I don't really have spare cash right now. I also hear that it's easier to do plugs on the car with the UIM off, so I would do those if I ended up cleaning and rebuilding them, which is even more money. Kinda opening up a can of worms, eh?
Any suggestions? Right now I'm thinking that I'm going to replace the DPFE if I can find it. Also thinking that I'll clean the throttle body and see if that helps? I appreciate any help that anyone has to offer. I've been playing around with this stupid CEL for awhile now. Can't do any mods until this thing is atleast running good stock!
Technical Description
Insufficient EGR Flow
What does that mean?
EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR.
Symptoms
You may notice drivability problems such as pinging (a.k.a. pre-ignition knock) when the engine is under load or the vehicle is at higher speeds. There may also be other symptoms.
Causes
A code P0401 most likely means one or more of the following has happened:
* The DPF (differential pressure) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (most likely carbon buildup)
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum
Possible Solutions
In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.
* Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's. There should be a noticable difference in RPM's with the EGR open
* Clean out the EGR valve to remove deposits
* Replace the DPF sensor
* Replace the EGR valve
I have a 2002 Cougar Sport with about 60k miles on it. I've had a CEL on for about 3k now. It has a rough idle, has been sluggish, and I'm getting about 17mpg. I tried cleaning the EGR valve, nothing. So I replaced it, still nothing.
I've read that it could be the DPFE sensor, but I can't find it. I've read this how to ( http://www.newcougar.org/forums/showthread.php?t=2193&highlight=dpfe ), to replacing the DPFE, but I don't see it anywhere. Is it different in the 2002 year? Does the 2002 even have a DPFE?
I've also read that you can try cleaning and rebuilding the upper and lower intake manifolds ( http://www.contour.org/mods/mods.php?s=howto&displayid=17 ). I've heard that this could fix performance problems and CEL. But, it seems like a lot of work and money to do if it's not going to fix anything or make a difference. I don't really have spare cash right now. I also hear that it's easier to do plugs on the car with the UIM off, so I would do those if I ended up cleaning and rebuilding them, which is even more money. Kinda opening up a can of worms, eh?
Any suggestions? Right now I'm thinking that I'm going to replace the DPFE if I can find it. Also thinking that I'll clean the throttle body and see if that helps? I appreciate any help that anyone has to offer. I've been playing around with this stupid CEL for awhile now. Can't do any mods until this thing is atleast running good stock!
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