I replaced the EGR valve and the DPFE module and cleared codes and within a day P0401 code comes back! BTW I have a 96 Ranger 2.3
Help!!!!

 

chilton manuel says
EGR flow insufficient
but im not sure why it would do the samme thing after replacing the old one

 

I have no clue! Hoping someone would chime in

 

Anyone!!!

 

PCM commands the EGR solenoid to open when @ cruising speeds. Solenoid opens, routing vaccum to pull the egr valve open, so exhaust gases get passed into the intake.

DPFE has two hoses, one is Ref pressure, the other is Signal. When the PCM opens the EGR solenoid and the EGR valve opens, exhaust gas pressure is felt in the Signal hose to the DPFE. This creates pressure against a diaphragm that produces the electrical signal.

http://www.tomco-inc.com/Tech_Tips/ttt33.pdf

Your issue could be a bad hose to the DPFE, bad EGR solenoid (not opening), or carbon is blocking EGR exhaust gas flow.

 

I've seen more bad DPFE sensors for that code, and once had to go through about 4 new sensors to find a good one. Even if you just replaced it, it wouldn't hurt to double check it.




"1996 Ford Ranger 2.3L - Confirmed Fix

Vehicle Description: 1996 Ford Ranger 2.3L, Vin A, Eng Cfg L4

Mileage: 161000



Customer Concern: Setting trouble codes P0401 and P1408. The EGR vacuum regulator (EVR) does work when grounded and the Exhaust Gas Recirculation (EGR) valve opens.



Tests: 1. Check the Differential Pressure Feedback EGR (DPFE) sensor voltage Key On Engine Off either on a scanner or by back probing the Brown/Light Green (BR/LG) wire at the DPFE sensor. The voltage should read roughly 0.4-1.1v depending on the sensor.

2. If the voltage is not correct (either above 1.1v or less than 0.4v), verify the Brown/White (BR/WH) wire is a good ground and that the Gray/Red (GY/RD) wire shows a good ground. Also make sure all pin connections are tight. If so, replace the DPFE sensor and retest.

3. If the voltage is correct Key On Engine Off, use a hand vacuum pump and apply 8" Hg vacuum to the "REF" port of the DPFE sensor. The voltage should increase to at least 4v. If it does not, replace the sensor and retest.



Potential Causes: Differential Pressure Feedback EGR (DPFE) sensor

** Confirmed Fix **
Replaced Differential Pressure Feedback EGR (DPFE) Sensor"

Copyright 2009 Identifix, Inc.

 

I just went through this with my 4.0. Clean the egr tubes. You will more than likey have carbon build up in the hoses. Disconnect it from the exaust to the intake and clean it really good. And make sure you get the new plastic dpfe sensor not the old metal ones. There is alot of mousture build up in the egr system and if there is alot of carbon buildup in the lines itll clog every time. Also search all the egr lines for small holes. Also I think you will also have a vacum sylinoid that will create the vacum pressure needed to open the egr, but am not sure on the 2.3

 

Much appreciated!!!

 

Don't think the 2.3 have em???

 

Yea didnt think so. I have the 4.0 sohc. This code was a nightmare for me but got it done. I will have to go check the 2.3 out in a '96

 

my 01 does the same. had egr repalaced... the only thing it is is the damn DPFE sensor. i replace mine every 6 months...its cheezy... always goes out... ohwell. $90 a year isnt bad.lol

 

i'm having the same problem with my 1996 with 2.3 also. Now i'm over a month late on getting the emissions test done because it failed saying P0401. I'v replaced EGR vlave, EGR selonoid, egr pressure feedback sensor, both o2 sensors, ect. Can anyone else help me out on what else to replace or check. Thanks

 

how are your spark plugs and injectors i had a bad injector problem cause all three codes p0401,p0173, and p0174 once i replaced injectors i have never gotten the codes again. could be something way different on your truck though so dont hold me to it haha. just throwing in my 2 cents!

 

well I replaced plugs and wires probably about 30K miles ago....haven't changed injectors since i'v owned truck...probably original injectors. Truck has 154K miles....But as far as i'm aware all injectors are working fine

 

oh ok yeah i could tell one of my injectors were bad because when i started her up i had to give it some gas.

 

im having same trouble with my 2.3 replaced egr valve . and the sens, gunnah take everyones advice and clean the hose, will update thnks ppl!

 

SUGGESTION:::REPLACE THE DPFE WITH A OEM, MOTORCRAFT PART.

These sensor are very delicate, and often times aftermarket parts just dont do it.

Here is a link to a place you can get the OEM part for 46.95

Ford DPFE Sensor

Motorcraft part # DPFE15
Good luck.