Code p0401

2004 FORD EXPLORER

98,000 MILES • 4.0L • 6 CYL • 2WD • AUTOMATIC

MIKE421$$

MEMBER
2 POSTS

Hi, I have the vehicle listed above and I have a code “p0401” EGR valve insufficient flow, I cleaned the throttle and the idle is moving fine but i still have that code. What should I first do to fix it?

Dec 3, 2018 at 3:13 PM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

Good evening,

The most common cause for this code is the DPFE sensor. Very common failure.

It is mounted on top of the EGR which is under the plastic cover. It is simple to replace and the parts stores should stock them.

Roy

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Dec 3, 2018 at 4:18 PM

MIKE421$$

MEMBER
2 POSTS

What would be my next step after fixing this and I still get the code?

Dec 3, 2018 at 4:33 PM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

One step at a time.

In 99% of all the Fords I have done, that took care of it. The other 1% was the hoses were melted but you do not have that issue.

In rare cases, a clogged catalytic converter will cause this but you would have other issues.

Roy

Dec 3, 2018 at 4:41 PM

BMDOUBLE

✓ASE Certified Mechanic
1,139 POSTS

Agreed! If the DPFE sensor has not been replaced, I would do it for sure.

Dec 5, 2018 at 5:38 PM

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