I've had the engine code P0401 ( EGR Flow Insufficient ) for a month or so now and I can't fix it!!!! I've tried doing everything mentioned on here about the EGR valve and DPFE sensor and the light is still on. I've cleaned them, replaced the DPFE sensor and reset the ECU. After I reset the ECU the light stayed off for about a day then came back on. The EGR valve isn't stuck, I took it off and if you suck on it the valve works.
I need to get my Ranger inspected within the next month so that's why I'm mad.
My buddy Rudy (rudeman85) got an 03 with 4.0 recently and it has no EGR at all, it's pugged up on the motor body where it would be. Is it possible for me to take my EGR off and plug it up like his? But what would I do with the wiring?... and it would probably make it run bad because there's nothing hooked up to the wiring. Can I get a later model ECU from a Ranger that runs without the EGR?
any help please!!!!!!!?????

 

If you try to eliminate the EGR, you will have continue to have a CEL all the time.

Here are the possibilities for a P0401 according to Ford:

::: * EGR valve stuck
::: closed

::: * EGR valve leaks
::: vacuum

::: * EGR flow path
::: restricted

::: * EGRVR circuit
::: shorted to PWR

::: * VREF open to D.P.F.
::: EGR sensor

::: * D.P.F. EGR sensor
::: downstream hose off
::: or plugged

::: * EGRVR circuit open
::: to PCM

::: * VPWR open to EGRVR
::: solenoid

::: * D.P.F. EGR sensor
::: hoses both off

::: * D.P.F. EGR sensor
::: hoses reversed

::: * Damaged EGR orifice
::: tube

::: * Damaged EGRVR
::: solenoid

::: * Damaged PCM

 

If I eliminate the EGR can I get a newer ECU from a truck that has no EGR to begin with?
Would eliminating it be plausible or worth it?
What should I do?

From the list that is posted do you know of any that are more common to check?

 

I wouldn't bother eliminating the EGR. It would be costly and illegal.

IMO, the most likely causes of P0401 would be:

Bad DPFE sensor <- 99% probability
Reversed hoses on the DPFE
Damaged wiring to the DPFE
A leak somewhere in the EGR tubing
A bad EGR solenoid valve

 

I replaced my DPFE sensor with one from a salvage yard that I was at getting some other parts, the truck had 12k miles on it so it shouldn't be bad, but it didn't take care of the code.
I'll run over the hoses to see if any are loose.
As for the wiring, there's no good way to check that.
thanks....i'll get back after I go over the stuff mentioned

 

That is a large assumption for a DPFE sensor. I had one die at 15,000.

 

Should I buy a new DPFE sensor then?

 

The ideal thing to do would be to trade with someone for a few days and try it. That way you wouldn't need to buy one unnecessarily.

Ford used that same DPFE sensor across many engine families in many car and truck model lines. The connectors and mounting style do sometimes vary by year though. To swap with your 2001, I think that most EGR-equipped Fords from about 2001~2003 should have that same small Kavlico DPFE sensor.

 

Isnpection or Emissions?

Well, if you're short on time, there a quick fix. If it's inspection, you might consider pulling the light out. You should be able to just sneak by like that. If it's emissions, my 87 had no EGR for my past three emissions and I had no problem.

 

My INSPECTION is in June.

 

Alright, alright. Some people switch the words around, so I just wanted to make sure it was inspection. Well, if you can't get it fixed by then, just pull the light out. In Maryland, they don't pull up codes from you vehicle, so as long as it's still there and connected, and you pull the light out, they won't notice.