have a 05 f150 stx 4.6. has 71,000 miles. was at sonic and check engine light came on. had it read and that said insufficient egr flow. i have researched it a lil bit and seen you can check it with a vacuum. and by cleaning the ports. well got cpl questions before i work on it. my egr valve has a sensor right on top of it and 2 hoses hooked on side of them, also like a 5/16 hose hooked kinda to the side of the valve. where would i hook up the line 2 see if egr is working? also when removing the throttle body im gna need the gaskets im sure right? and also do i clean the hoses that also run 2 egr valve? thanks. id like 2 get it fixed maybe sat or sun. appreciate the help

 

i removed the egr valve, throttle body and cleaned all the ports with tb cleaner. was on the dirty side. put it back 2gether and drove it a few miles and bam it came back on and same code. insufficient egr flow. could the egr valve be bad? i dont know where 2 hook the vacuum line up 2 my egr has 2 hose connections. so i actually pulled them both 1 at a time and sucked pretty hard and truck really didnt try 2 die or anything. any advice would be awesome.

 

Take vacuum gauge and find the EGR on the top of the EGR you'll see a vacuum line on it, take that vacuum line off and put your vacuum gauge on the top.... Start the vehicle and pump thevacuum gauge as the vacuum is increased your idle should change and in some cases (depending on the vehicle) it may die, that means the EGR is working. If it is working 99% of the time it's the DPFE sensor (the sensor mounted where you see the two rubber lines / it's the sensor attached to those) Also check the rubber lines and make sure they are attached and in good shape, if not thats the cause. If the lines are good then I'd replace the DPFE sensor. If you do not have a vacuum pump take it off and hit the two ports on your palm (the ports of the sensor) and see if water comes out which is another indicator of a sensor needing to be replaced (water wigs out the sensor and in my experience I've never been able to clean one out and revive it) I've replaced dozens of DPFE's due to that code and have only had a wiring issue once and a plugged EGR once, it's very commen on Ford's to be bad.

 

k i just wanna make sure i hook to the right part on egr. mine has the 2 hoses hooked to the sensor then go and meet into one hose that plugs into the intake manifold. there is another hose about 5/16 thats about maybe 3 inches long and hooks in from lower part of egr to upper kinda on the side. hose does a horshoe bend. thats all thats hooked into it. would ya happen 2 know which one i hook into?

 

The two hoses that go to the sensor is to monitor the flow (that sensor is the DPFE) CHECK THOSE HOSES IF OK = no need to replace. If bad replace and clear the code and drive to see if it comes back........... The EGR only has 1 vacuum line on it, WHICH IS ON THE TOP. Take that line off and HOOK THE VACUUM GAUGE THEIR. Then apply vacuum and test. Im not sure if you are familiar with what the egr is????? The tube where the two vacuum lines are is not the EGR thats just the tube, the EGR is the round part with just one vacuum on top.

 

unless im just looking at something crazy, my egr has no hose directly on top. the 2 hoses do hook up to the dpfe the sensor (which is directly on top of egr). i have looked and looked under google and all the egr valves ive seen do have a hose on top and mine doesnt. im 100 percent sure thats what it is. its hooked to side of intake looks like a lil alien ship so to speak. mounts up with 2 bolts has exhaust pipe running into the back of it. also i called ford just 2 get a price on a the dpfe sensor just to be curious. here is the exact words they told me. they said sir the sensor is built in your throttle body and is 189.00 bucks. i thot they were crazy

 

I'll look at a manual and see if they have switched the design or not.

 

P0401 - Exhaust Gas Recirculation (EGR) Flow Insufficient Detected
Description: The EGR system is monitored during steady state driving conditions while the EGR is commanded on. The test fails when the signal from the differential pressure feedback EGR (DPFEGR) sensor indicates that EGR flow is less than the desired minimum.
Possible Causes: Vacuum supply
EGR valve stuck closed
EGR valve leaks vacuum
EGR flow path restricted
EGRVR circuit shorted to PWR
VREF open to DPFEGR sensor
DPFEGR sensor downstream hose is off or plugged
EGRVR circuit open to the PCM
VPWR open to EGRVR solenoid
DPFEGR sensor hoses are both off
DPFEGR sensor hoses are reversed
Damaged EGR orifice tube
Damaged EGRVR solenoid

Diagnostic Aids: Carry out the key on engine running (KOER) self-test and look for DTC P1408 as an indication of a hard fault. If P1408 is not present, look for contamination, restrictions, leaks, and intermittent faults.
Application Key On Engine Off Key On Engine Running Continuous Memory
Vehicles with an EGR system module (ESM) — — GO to HH15 .
All others — — GO to HE36 .


HH15 DTC P0401: CARRY OUT THE KOER SELF-TEST
Note: Diagnose and repair all circuit fault DTCs before diagnosing range/performance or flow concerns.

Carry out the KOER self-test.
Is DTC P1408 present?
Yes No
GO to HH16 . GO to HH17 .

HH16 DTC P1408: CHECK THE VREF VOLTAGE TO THE ESM
Key in OFF position.
ESM connector disconnected.
Key in ON position.
Measure the voltage between:

( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
VREF - Pin 2 Negative terminal


Is the voltage between 4.5 V - 5.5 V?
Yes No
GO to HH17 . GO to C1 .

HH17 CHECK THE EVR SOLENOID VACUUM
ESM connector connected.
Disconnect the EVR vacuum source hose.
Connect a vacuum gauge to the EVR vacuum source hose.
Key on engine running.
Monitor the vacuum gauge.
Is the manifold vacuum greater than 34 kPa (10 in-Hg)?
Yes No
GO to HH18 . REPAIR as necessary.

HH18 SIMULATE THE DPFE SENSOR SIGNAL WITH A VACUUM PUMP
Key in OFF position.
Disconnect the downstream DPFE sensor port hose at the ESM.
Verify hose and port is clear and free of obstructions.
Connect a vacuum pump to the downstream DPFE sensor port.
Key in ON position.
Access the PCM and monitor the DPFEGR PID.
Apply 27 - 30 kPa (8 - 9 in Hg) vacuum to the DPFE sensor and hold for 10 seconds.
Quickly release vacuum.
The DPFEGR PID voltage must be between 0.2 and 1.3 volt with the key ON and no vacuum applied.
The DPFEGR PID voltage must increase to greater than 4 volts with the vacuum applied.
The DPFEGR PID must drop to less than 1.5 volts in less than 3 seconds when the vacuum is released.
Does the DPFEGR PID voltage indicate a fault in the DPFE sensor?
Yes No
INSTALL a new ESM. CONNECT all the hoses.

GO to HH19 .

HH19 CHECK THE EVR SOLENOID OPERATION
Key on engine running.
Engine at normal operating temperature.
Allow the engine idle to stabilize.
Access the PCM and monitor the RPM PID.
Access Output State Control.
Increase the EVR duty cycle while monitoring the RPM PID.
Does the RPM decrease or the engine stall as the EVR duty cycle is increased?
Yes No
Unable to duplicate or identify the fault at this time.

CHECK for the presence of carbon build-up in the EGR passage. GO to HH20 .

HH20 CHECK FOR THE PRESENCE OF CARBON BUILD-UP IN THE EGR PASSAGE
Note: In certain vehicle applications, carbon build-up may occur downstream of the ESM. An inspection is required to make sure the passage in the upper intake manifold plenum chamber behind the ESM is open to allow exhaust gas flow.

Key in OFF position.
Remove the ESM. For additional information, refer to the Workshop Manual Section 303-14 Electronic Engine Controls.
Disconnect the air inlet tube from the throttle body. For additional information, refer to the Workshop Manual Section 303-12 Intake Air Distribution and Filtering.
Prop open the throttle body.
Apply regulated shop air to the EGR port at the location where the ESM attaches to the upper intake manifold.
Is a restriction concern present?
Yes No
CLEAN the EGR port as necessary and reinstall the ESM. INSTALL a new ESM.

HH21 DTCS P0403 AND P1409: CHECK THE EVR SOLENOID OPERATION
Key on engine running.
Engine at normal operating temperature.
Allow the engine idle to stabilize.
Access the PCM and monitor the RPM PID.
Access Output State Control.
Increase the EVR duty cycle while monitoring the RPM PID.
Does the RPM decrease or the engine stall as the EVR duty cycle is increased?
Yes No
Unable to duplicate or identify the fault at this time.

GO to Z1 . GO to HH22 .

HH22 CHECK THE VPWR VOLTAGE TO THE EVR SOLENOID
Key in OFF position.
ESM connector disconnected.
Key in ON position.
Measure the voltage between:

( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
VPWR - Pin 4 Negative terminal


Is the voltage greater than 10.5 V?
Yes No
GO to HH23 . REPAIR the open circuit.

HH23 CHECK THE EVR SOLENOID COIL RESISTANCE
Key in OFF position.
Measure the resistance between:

( + ) ESM Connector, Component Side ( - ) ESM Connector, Component Side
VPWR - Pin 4 EGRVR


Is the resistance between 26 ohms - 40 ohms?
Yes No
GO to HH24 . INSTALL a new ESM.

HH24 CHECK THE EVR CIRCUIT FOR AN OPEN IN THE HARNESS
PCM connector disconnected.
Measure the resistance between:

( + ) ESM Connector, Harness Side ( - ) PCM Connector, Harness Side
EVR - Pin 1 EVR


Is the resistance less than 5 ohms?
Yes No
GO to HH25 . REPAIR the open circuit.

HH25 CHECK THE EVR CIRCUIT FOR A SHORT TO POWER IN THE HARNESS
Key in ON position.
Measure the voltage between:

( + ) PCM Connector, Harness Side ( - ) Vehicle Battery
EVR Negative terminal


Is the voltage less than 1 V?
Yes No
GO to HH26 . REPAIR the short circuit.

HH26 CHECK THE EVR CIRCUIT FOR A SHORT TO GND IN THE HARNESS
Key in OFF position.
Measure the resistance between:

( + ) PCM Connector, Harness Side ( - )
EVR Ground


Is the resistance greater than 10K ohms?
Yes No
INSTALL a new PCM. REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM). REPAIR the short circuit.

HH27 EGR DIAGNOSIS BY SYMPTOM: CHECK FOR EGR FLOW WITH THE EVR VACUUM HOSE DISCONNECTED AND PLUGGED
Note: Carry out the KOER self-test. Repair any other DTCs.

Possible causes for EGR flow at idle with no related DTCs:
EGR valve not fully seating.
EVR solenoid vent restricted.
Damaged EVR solenoid.
Disconnect and plug the EVR vacuum source hose.
Key in ON position.
Access the PCM and monitor the DPFEGR PID.
Record the PID voltage.
Key on engine running.
With the engine at idle, observe the DPFEGR PID voltage.
Compare to engine OFF voltage.
An increase in DPFEGR PID voltage at idle indicates EGR flow.
Is the idle DPFEGR PID voltage greater than 0.15 volt when compared to the KOEO DPFEGR PID voltage?
Yes No
REMOVE and INSPECT the ESM for signs of contamination, unusual wear, carbon deposits, binding or other damage.

REPAIR as necessary.

If no concerns are present, INSTALL a new ESM. INSPECT the EVR solenoid vent for blockage.

To continue symptom diagnosis, REFER to Section 3, Step 3: No DTC(s) Present Symptom Charts.

 

You may be forced to take to the dealer or a shop and pay for an hour of diagnosis, as this one is fairly complex. I can't see a real good picture to see if you can use vacuum to open the port or not. Ford has been getting pretty complex with a lot of new vehicles and the fact most use more modules it becomes harder to diagnose unless you have a very good understanding of electrical. From what I can tell is the module is on top (which looks to control the EGR opening and closing rather than vacuum) and the two hoses go directly to the DPFE.

 

i appreciate ya f350 for the researching ya did for me. im prolly gna drop it off and have them diagnose the problem for me, and i will put the part on. im gna order a repair manual (i should already have since i have one for all my other vehicles). just hope they dont (break it off in me) lol.. ty

 

Sorry I couldn't help you better..... Definately post what it ended up being when you find out.

 

hey folks sorry i havent got back with you. had some things going on, but anyways. im replying about the truck the the p2401. i put a egr valve on it and works awesome now. no more codes. ford wanted dealer locally wanted a crazy amount of money 2 put it on. took no more than 30 minutes for me 2 do it. just wanted 2 get back with yall on it. thanks all