P1401 after intake manifold job

NJaykaplan

Registered
Can't find any vacuum leaks with spray, looked around for any loose or broken vacuum lines. Not sure if i should change my dpfe sensor since its original or not. I changed the egr gasket, thats all when i was back there. The code is for high pressure and i don't believe that a broken or disconnected line would do a high voltage code, i would have believed it to throw low voltage. Any advice is helpful, i dont know how to test my egr system.
 
The high voltage signal implies a high differential pressure signal.

HE10 DTC P1401: VERIFY DIFFERENTIAL PRESSURE FEEDBACK EGR (D.P.F. EGR) SENSOR VOLTAGE

Diagnostic Trouble Code (DTC) P1401 indicates that Self-Test has detected DPFE SIG circuit input above the maximum.

Possible causes:

-- DPFE SIG open.

-- DPFE SIG shorted to VREF or PWR.

-- VREF shorted to PWR.

-- SIG RTN open.

-- Damaged D.P.F. EGR sensor.

-- Damaged PCM.

Key on, engine off.

Access D.P.F. EGR sensor (formerly DPFE) with a Scan Tool.

Is DPFEGR PID voltage greater than 4.0 volts?

Yes
The D.P.F. EGR sensor voltage is greater than the acceptable maximum. GO to «HE11».

No
The fault that produced DTC P1401 is intermittent. GO to «HE19».

HE11 CHECK DPFE SIG FOR SHORT TO PWR

Key off.

Disconnect D.P.F. EGR sensor vehicle harness connector.

Key on, engine off.

Measure voltage between DPFE SIG circuit at the D.P.F. EGR sensor vehicle harness connector and battery ground.

Is voltage greater than 10.5 volts?

Yes
The D.P.F. EGR sensor voltage input is indicating a short to PWR. GO to «HE12».

No
GO to «HE13».

Looks like it could be a wiring fault? Or a faulty DPFE?
 
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Bet you either didn't connect the high temp hoses or put them on backwards. On the DPFE sensor.
 
I had one of my close friends i've known for years who is a certified mechanic do the work for me, i would consider myself mechanically retarded, but i love diagnosing my own issues on the car. Is there a way for me to see if anything is disconnected without taking the throttle body out? I don't have anyone close who knows mark viiis very well, otherwise i would spend the extra cash for the experience with the lincolns. Ive been broke and i haven't taken it apart with him, mainly because i cant afford the sensor until i get paid if that is what is wrong. I really was thinkin something was disconnected, or broke in reassembly, this weekend most likely i'll have the money to have everything looked at and buy the sensor if thats what i need.
 
I noticed the pvc wasn't in all the way, and i believe that got rid of my bank 1 and bank 2 lean codes. So far no p1401 either, i'll check back later or tomorrow after the P1000 code goes away, so i know it did all its checks already.
 
Cool. You don't have to take the throttle body off to check the DPFE sensor on the back of the driver side cylinder head, although a pocket mirror helps.
 
I'm now thoroughly confused, i now have P0401. I might just replace the sensor in a week and see if it makes a difference, once i have money together. I really need to have someone use a vacuum pump and test the EGR out.
 
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