Egr Flow Insufficent

FORD F-150
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HAWGWILD
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  • 1 POST
I have a 1999 F150 4.6 Triton 4x2
I keep getting code 401...Egr Fow Insufficent
I have cleaned the egr port, replaced the egr valve,
replaced the devp sensor and the vaccum solenoid.
the code may stay gone for 1-2 days then return or it may come back upon cold start. it may stay out all day of driving then return after the truck has sat for a few hours. please can someone point me in the right direction.?
Oct 23, 2007 at 5:33 AM
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RASMATAZ
  • ✓Experienced Mechanic
  • 75,988 POSTS
Common EGR problem with many Fords is a bad DPFE (differential pressure) sensor. The DPFE sensor is part of the EGR system and senses EGR flow when the EGR valve is open.

It provides a feedback signal to the engine computer so it can vary EGR flow to meet changing engine loads. The DPFE sensor is usually mounted on the engine and is connected to the pipe that runs from the exhaust manifold to the EGR valve with two rubber hoses.

When the sensor goes bad, the Check Engine light comes on and typically sets any or all of teh following fault codes: P0171 & P0174 (lean codes), and/or P0401 (insufficient EGR flow). Nine out of ten times, the fault is not a bad EGR valve or a vacuum leak, but a bad DPFE sensor. A replacement costs about $112 at Ford, or about $48 at an aftermarket auto parts store
Oct 23, 2007 at 8:19 AM
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SKIBO1
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also check and make sure you are getting vacuum to the egr valve as this can also cause this code
Oct 23, 2007 at 12:16 PM
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