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Idahome
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Never buy re manufactured starters, alternators, power steering pumps, etc
You want NEW
P0400 = EGR flow malfunction
This means that during self test of the EGR system something went wrong
Then the light went away
this means that during the next self test the problem was not there so the light and code were cleared
Expect it to come back, although EGR codes are the ones that pop up and then clear themselves the most. Typically they will come back when those same conditions are experienced again (altitude, fuel octane, driving conditions, etc), it could be days weeks or years.
Typically a EGR flow issue is a blocked or cut EGR feed tube to the DPFE (differential pressure feedback sensor EGR)
I would not suspect a faulty EGR valve just yet, instead I would inspect the EGR system, check the hoses leading to the DPFE, check the DPFE for plugged passages, have a look see at all wiring connections on the EGR, clean everything up and put it back together.
Typically the rubber EGR hoses and DPFE fail long before the actual EGR valve itself.
Last edited on Fri Jan 24th, 2020 09:28 am by 410customs
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I build custom RBV, specializing in drivetrain conversions, wiring, suspension and complete custom trucks