P0401 CODE - HELP!!!!! 11-13-10
Thread Starter
|
New User
Joined: Nov 2010
Posts: 1
Likes: 0
P0401 CODE - HELP!!!!! 11-13-10
Have read quite a few of your posts regarding the EGR insuffucient flow... Is there any way to get a schematic of the engine (V-8) to more easily see where this stuff is located?
Replaced all of the O-sensors to the tune of 200+ and it still failed inspection. Had no idea about the EGR ports/valves. While I'm very mechanically inclined for most repairs on vehicles and other equipment, I associate things better with an illustration.
I've got a deadline on getting this fixed and since forced into retirement, hope to correct this problem myself since it may be a port, hose, etc. Just need to see it on paper if at all possible.
Any suggestions are much appreciated! Thanks in advance!
Replaced all of the O-sensors to the tune of 200+ and it still failed inspection. Had no idea about the EGR ports/valves. While I'm very mechanically inclined for most repairs on vehicles and other equipment, I associate things better with an illustration.
I've got a deadline on getting this fixed and since forced into retirement, hope to correct this problem myself since it may be a port, hose, etc. Just need to see it on paper if at all possible.
Any suggestions are much appreciated! Thanks in advance!
Freshman User
Joined: Nov 2010
Posts: 34
Likes: 0
Restriction in the EGR passages, usually caused by carbon buildup this would be my guess or Differential EGR Pressure Feedback Sensor (DPFE) this would another guess i would try them out first
The EGR Valve is defective
Lack of proper vacuum or electrical signal to the EGR valve
Malfunctioning EGR Vacuum supply solenoid
Lack of proper EGR system feedback to the computer from the:Manifold Absolute Pressure Sensor (MAP
EGR Valve Position Sensor (EVP)
EGR Temperature Sensor
The EGR Valve is defective
Lack of proper vacuum or electrical signal to the EGR valve
Malfunctioning EGR Vacuum supply solenoid
Lack of proper EGR system feedback to the computer from the:Manifold Absolute Pressure Sensor (MAP
EGR Valve Position Sensor (EVP)
EGR Temperature Sensor
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
If you replaced the OX sensors trying to fix a 401 code, better stop doing those things because you will waist your money.
Ox sensors and EGR are not at all related.
The 401 code is a low flow test failure in the EGR system.
The EGR port behind the EGR valve may be plugged.
The restriction the DPFE measures across may be blocked.
The DPFE may be faulty.
The EGR may not be operating.
Any one or more faults will fail a low flow test.
The trick for you if you are going to attend to you truck's fault codes is to learn about how the systems work so you know what you are working with.
It's a computer system.
The codes do not tell you what part to replace.
You need to chase the system with tests to determine what is good and what is not.
Sorry it's not simpler for you.
Good luck.
Ox sensors and EGR are not at all related.
The 401 code is a low flow test failure in the EGR system.
The EGR port behind the EGR valve may be plugged.
The restriction the DPFE measures across may be blocked.
The DPFE may be faulty.
The EGR may not be operating.
Any one or more faults will fail a low flow test.
The trick for you if you are going to attend to you truck's fault codes is to learn about how the systems work so you know what you are working with.
It's a computer system.
The codes do not tell you what part to replace.
You need to chase the system with tests to determine what is good and what is not.
Sorry it's not simpler for you.
Good luck.
Posting Guru
Joined: Oct 2008
Posts: 1,145
Likes: 1
From: Hernando Ms
Had the same issue on my 97 4.2...turned out to be the DPFE sensor.The OEM was some sort of metallic construction,and was indeed corroded to the point of being plugged up.
The replacement was plastic,and once I replaced it,the fault went away.
Perhaps you could "Google" "Ford DPFE Sensor" and you will get an idea how to identify it...Also,you can go to RockAuto Auto Parts and enter your vehicle info.Look in the emissions section,and click on DPFE sensor.You will likely get about 5 choices,and there will be a blue info icon..click on it,and youll see what it looks like.
My replacement came from rockauto,and while I dont usually recommend "aftermarket brands" it worked flawlessly.
BTW Welcome to the forum!
The replacement was plastic,and once I replaced it,the fault went away.
Perhaps you could "Google" "Ford DPFE Sensor" and you will get an idea how to identify it...Also,you can go to RockAuto Auto Parts and enter your vehicle info.Look in the emissions section,and click on DPFE sensor.You will likely get about 5 choices,and there will be a blue info icon..click on it,and youll see what it looks like.
My replacement came from rockauto,and while I dont usually recommend "aftermarket brands" it worked flawlessly.
BTW Welcome to the forum!
Thread
Thread Starter
Forum
Replies
Last Post
jmulvihill
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
28
Jan 11, 2013 07:44 PM
400inatruck
335 Series- 5.8/351M, 6.6/400, 351 Cleveland
1
Aug 20, 2011 02:35 PM
