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Discussion Starter · #1 ·
The Bronco failed inspection. Came up with the following codes:

-P0401 EGR flow insufficient
-P0714 System too lean

-P0307 Cylinder 7 misfire

I found the hose off the crossover tube in the back of the engine. That is fixed.

Took off the EGR and could not find any carbon. Any pictures of where to look for carbon? EGR seems to open / close easily.

Picked up a DPFE to replace, but cannot locate where is is mounted under hood. I've looked all over the internet, but cannot get info on where it's hidden. Any help on this would be appreciated.

The truck idles rough, but will smooth out from time to time. Runs real good otherwise.

What else should I be looking for?

Any help would be appreciated.
 

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Satyr of the Midwest
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Look at the tube behind the alternator, going from the exhaust manifold to the EGR valve. There should be two silicone hoses going from that tube to a metal box. That metal box is your DPFE sensor. It's more common for those two silicone hoses to burn through than for the sensor to go bad. Replacement hoses are relatively cheap, though. The carbon buildup usually occurs inside that metal tube, btw. Also, make sure the EGR valve holds vacuum, and that the plastic lines to it are intact.
 

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Welcome Broncster.
On some 5.0 Explorers, there's not a DPFE even though the parts books list it. These engines have an EGR position sensor instead. Maybe your Bronco is the same.

Here's a post I robbed from an Explorer forum. Maybe it'll help you locate your EVP sensor if so equipped.
Depending on which 5.0 you have, the positions of the EGR are close, but they are 2 different units. Look on the back of the upper plenum. You will either see a round aluminum item with an orange/red plunger in it that bolts to the 90 degree elbow, or you will see a plate that bolts to the upper plenum itself. The round aluminum one is the EGR Valve for that model. If it has the plate bolted directly to the plenum, that will be the backpressure transducer.

On both models, you will see a round black plastic cylinder unit. That is the EGR solenoid. There will be 2 tubes on it - one to the upper plenum and fuel regulator, and the other to either the EGR Valve or the backpressure trnsducer.

Either one you have, they are hard to see. They are on the back, and hard to work on. Mine had the EGR Valve on the elobw, and it was tight to get on/off.
 

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Discussion Starter · #4 ·
Found the DPFE - thank you very much-it was right where you said it would be. I must have looked right at it 100 times. Changed it and idles smoother. Also found white crud in the smaller of the two hoses which must have caused a blockage. Had the codes cleared. I'll let you know if this does the trick.
 

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Found the DPFE - thank you very much-it was right where you said it would be. I must have looked right at it 100 times. Changed it and idles smoother. Also found white crud in the smaller of the two hoses which must have caused a blockage. Had the codes cleared. I'll let you know if this does the trick.
I know this is over 2 years later, but did it work? I just ask because I popped this code on my (96 Bronco 5.8) drive up here to WA state a couple weeks ago and I notice the truck stumbling/bucking under low speed driving (25-35/40 mph) and surging at idle. I don't see it being much of a problem to pull the tube and clean it, but I have a hard time with buying a $60 sensor when that might not be the whole problem. You know, I work, wife stays home, kid on the way, blah, blah, blah.

Thanks.
 

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I know this is over 2 years later, but did it work? I just ask because I popped this code on my (96 Bronco 5.8) drive up here to WA state a couple weeks ago and I notice the truck stumbling/bucking under low speed driving (25-35/40 mph) and surging at idle. I don't see it being much of a problem to pull the tube and clean it, but I have a hard time with buying a $60 sensor when that might not be the whole problem. You know, I work, wife stays home, kid on the way, blah, blah, blah.

Thanks.
yo;
DTC PO401; Read the DPFE TEST @ http://www.tomco-inc.com/Tech_Tips/ttt36.pdf
Excerpts; read thru it all tho;
"There are a number of tests that the EGR system is put through. First the DPFE is checked. It is continuously monitored for opens or shorts. The OBD II system looks for the DPFE signal to exceed the minimum or maximum values. If it finds these values out of specs a DTC P01400 or 1401 will be set
The OBD II system also monitors the EGR flow rate. At a steady state condition when the engine load and speed are moderate and the EVR duty cycle is high the DPFE voltage is checked. It then compares this DPFE value to a stored desired DPFE value for those conditions. If the two values are inconsistent, the EGR flow is insufficient (Fig. 11). A DTC P0401 will be set for this condition. This test is also performed during a Key On Engine Running (KOER) test. If it fails during this test a DTC 1408 will be set..."

DPFE Sensor Testing in a 96 5.0;

"...DPFE comes in as .15 VDC during KOEO test between REF & Ground. TOMCO says it should read 0.45 +/- 0.25 volts for the .55 volt for this original Aluminum type sensor My Ford PCED/EVTM is frozen, so I can't view Ford's +/- values. &, when pulling REF hose off, fine particles fell out of DPFE. So, figuring DPFE Sensor is bad according to Ref voltage and particles...
by miesk5

Yes, your voltage of 0.15V on the DPFE line is a typical sign of a bad one. Try to obtain a Motorcraft replacement, as the retail part store pieces don't last..."
Source: by SigEpBlue (Steve) at FSB


Vacuum/Voltage Parameters & pics on both older Aluminum & Newer Plastic Version; MIESK5 NOTE: only 95 5.8L California models & all 96 have the DPFE Sensor instead of EGR Valve Position Sensor (EVP); Ford also calls the DPFE Sensor an EGR Pressure Valve; my 96's Ford pn is F4ZZ9J460-B; new Plastic replacement version is MOTORCRAFT Part #DPFE15
Source: by rockledge.home.comcast.net




===
Most of da time, because of hot exh gases flowing thru a little device, it is a failed DPFE sensor;
Before you buy a new one; ck the two high temperature silicone hoses that go from da EGT Tube's 2 small diameter tubes to the DPFE sensor. They are available at your local Ford Dealer. The dealer sells this special silicone hose by the foot ( I paid $10.00 for each hose & you trim it to exact length. PNs 1L3Z-9P761-AA - 1/4" for REF - Downstream hose (INTAKE) & 1L3Z-9P761-BA - 5/16" for Upstream hose (EXHAUST);

For da DPFE Sensor, The new DPFE sensor will be plastic as your original is still probably die cast metal; dealers in area want $150.00 for the DPFE Sensor and will not discount; so I bought the MOTORCRAFT DPFE15 thru Amazon w/free S&H for $60.00 and no tax;

Source: by miesk5 at FSB
 

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I know this is over 2 years later, but did it work? I just ask because I popped this code on my (96 Bronco 5.8) drive up here to WA state a couple weeks ago and I notice the truck stumbling/bucking under low speed driving (25-35/40 mph) and surging at idle. I don't see it being much of a problem to pull the tube and clean it, but I have a hard time with buying a $60 sensor when that might not be the whole problem. You know, I work, wife stays home, kid on the way, blah, blah, blah.

Thanks.
Mine through P0401 about 3 years ago and it was the DPFE...no problems since. Check out Rockauto.com before you buy one from the dealer or a parts store.

It won't hurt to try and clean out the silicone hoses prior to sensor replacement though.
 

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Thanks, guys. I'm heading on down to the ford dealer to get the silicone hoses as mine look like crap, and (glad I saw it now) a serpentine belt tensioner. I'm still not quite done moving, but once I find my meter and vacuum pump, I'll get right on that, too. Sometimes, I just wish it had a Holley.:crazy

Edit: it would appear that Ford, in their infinite wisdom, has obsoleted the right hoses for the thing, and all local parts stores carry is fuel injection type hose. I have my doubts as to whether it will hold up to the temperatures, which I assume can get pretty warm. I'm searching online, but can anybody point me in the right direction for a good replacement?
 
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