1996 Ford Bronco - To much EGR, or too little???

[nulife48]

I have a 1996 Ford Bronco, 5L (302), auto transmission, with 123k miles. I got a "check engine" light display one day. Took it to Checkers and had it tested. Code was P0401, for insufficient recirculated gas. I got a new EGR valve which included the gasket and two "washers" which act to restrict the flow into the EGR valve. They are slightly different size. Each had a different number stamped into it which I assume was cross sectional area of hole in the washer. I removed the old EGR valve and noticed there was no "washer" installed betw the tube and the EGR valve, so I did not install either of the washers provided. 3 minutes later I got the valve installed, engine running real nice and thought my problems were over. Not so fast. After 30 or 40 miles the check engine light came on again. No sweat - I had it tested and it was a P0402, too much recirculated gas. Hm....I installed the smaller of the two washers. Miles later same check engine light came on - but this time it was a P0401 - insufficient recirculated gas. So here I am laughing and wondering to do next. Now each time I touched the EGR valve, I disconnected the battery for safety adn to clear the memory. Also my EGR valve does not have the position sensor attached to the top of it, it is located in some as yet unknown place.

I ordered a new EGR valve position sensor from Autozone, but I need some help here. Where the heck is it? I looked everywhere, but can't find it. Hopefully it is not betw the rear of the engine and the firewall. It appears to be about 2 inches tall, black plastic, a plug for the electrical connection and at least one connection for a hose - maybe vacuum line??? Dealer charges $128 and I paid $23 plus ship/tax, so I am in the right price range.

2nd question is if I can get that sensor installed and the light comes on again, too little or too much recir gas, any ideas what to replace next ? EGR pressure sensor maybe???

The truck runs real nice now, mileage went up 2 maybe 3 mpg. If light comes on, I might just ingore it with some black tape. Bad idea?

Thanks in advance for your help. YOu guys provided some good info the last time.

 

[nulife48]

I have a 1996 Ford Bronco, 5L (302), auto transmission, with 123k miles. I got a "check engine" light display one day. Took it to Checkers and had it tested. Code was P0401, for insufficient recirculated gas. I got a new EGR valve which included the gasket and two "washers" which act to restrict the flow into the EGR valve. They are slightly different size. Each had a different number stamped into it which I assume was cross sectional area of hole in the washer. I removed the old EGR valve and noticed there was no "washer" installed betw the tube and the EGR valve, so I did not install either of the washers provided. 3 minutes later I got the valve installed, engine running real nice and thought my problems were over. Not so fast. After 30 or 40 miles the check engine light came on again. No sweat - I had it tested and it was a P0402, too much recirculated gas. Hm....I installed the smaller of the two washers. Miles later same check engine light came on - but this time it was a P0401 - insufficient recirculated gas. So here I am laughing and wondering to do next. Now each time I touched the EGR valve, I disconnected the battery for safety adn to clear the memory. Also my EGR valve does not have the position sensor attached to the top of it, it is located in some as yet unknown place.

I ordered a new EGR valve position sensor from Autozone, but I need some help here. Where the heck is it? I looked everywhere, but can't find it. Hopefully it is not betw the rear of the engine and the firewall. It appears to be about 2 inches tall, black plastic, a plug for the electrical connection and at least one connection for a hose - maybe vacuum line??? Dealer charges $128 and I paid $23 plus ship/tax, so I am in the right price range.

2nd question is if I can get that sensor installed and the light comes on again, too little or too much recir gas, any ideas what to replace next ? EGR pressure sensor maybe???

The truck runs real nice now, mileage went up 2 maybe 3 mpg. If light comes on, I might just ingore it with some black tape. Bad idea?

Thanks in advance for your help. YOu guys provided some good info the last time.

UPDATE _ I FOUND THE EGR POSITION SENSOR AKA DFPE. What threw me was the picture from autozone shows a black plastic piece while the one my truck is metal, maybe aluminum. It is located just to the right of the throttle linkage on drivers side. So just maybe 8 or 10 inches away from the EGR valve.

I have done a lot reading on the forums and every so often I come across someone who actually worked on these systems at a Ford dealer. He will typically say they rarely need to replace the EGR valve, it most likely is the position sensor that goes bad. EGR valves last a long time. The DPFE is subject to moisture also I read. Well, just need to wait until I get the sensor from Autozone and install. Hope that does it.

 

[BLADE262US]

Well you should never quit reading and asking questions is always good . I am very familiar with the EEC IV fuel injection system and what it sounds like youve found over there is the TPS it is black and has a pigtail coming out of it with 3 wires and a plug in , Thats not what your looking for if your getting an EGR sensor code . The EGR position sensor is located directly on top of the EGR valve it is what the wires plug into . If I remember right theres 3 pins in it and 2 or 3 small bolts that hold it to the top when you take these out it will pull straight up and out there is a plunger that sticks down into the EGR valve and as the valve moves it moves this plunger which is a variable resistor which is how it sends a signal back to the EEC . Hope that keeps ya from chaseing your tail /emoticons/[email protected] 2x" width="20" height="20" />

 

[miesk5]

yo! good research!

here is some more;

P0401 Possible causes:

Fault in vacuum supply to EGR vacuum regulator solenoid.

Damaged D.P.F. EGR sensor.

EGR valve stuck closed or iced.

EGR valve diaphragm leaks.

EGR valve or flow path restricted.

EGR vacuum hose off, plugged or leaks.

VPWR circuit open to EGR Vacuum Regulator solenoid.

EVR circuit to PCM open.

EVR circuit to PCM shorted to PWR.

Differential Pressure Feedback EGR (D.P.F. EGR) sensor pressure hoses both connected improperly.

D.P.F. EGR sensor pressure hoses reversed.

D.P.F. EGR sensor VREF circuit open.

Downstream pressure hose off.

Downstream pressure hose plugged.

Damaged orifice tube assembly.

Damaged EGR Vacuum Regulator solenoid.

Damaged PCM.

had same code in our 96 2 yrs ago and it was the DFPE

EGR Service Tips, Ford by SMP at smpcorp.com via web.archive.org

http://web.archive.org/web/20040610225422/...view/tt2q00.pdf

EGR Valve Position (DFPE) Sensor Operation & Testing, Ford by Tomco Inc. tomco-inc.com

http://www.tomco-inc.com/Tech_Tips/ttt19.pdf

btw, Tomco makes an EGR Tube Screen for 84-96, neat stuff! http://www.tomco-inc.com/Catalog/m1667t.pdf

one more thAng that will go the way of rust soon is the EGR Tube

for 84-96 Bronco & Fords PCI, Inc http://www.pciinc.com/index.cfm

can buy locally or direct

and the check valve rusts out as well, PCI has them incl AAP, AZ, etc.

 

[nulife48]

Well you should never quit reading and asking questions is always good . I am very familiar with the EEC IV fuel injection system and what it sounds like youve found over there is the TPS it is black and has a pigtail coming out of it with 3 wires and a plug in , Thats not what your looking for if your getting an EGR sensor code . The EGR position sensor is located directly on top of the EGR valve it is what the wires plug into . If I remember right theres 3 pins in it and 2 or 3 small bolts that hold it to the top when you take these out it will pull straight up and out there is a plunger that sticks down into the EGR valve and as the valve moves it moves this plunger which is a variable resistor which is how it sends a signal back to the EEC . Hope that keeps ya from chaseing your tail /emoticons/[email protected] 2x" width="20" height="20" />

I have seen pics of what you are describing - the position sensor is right on top of the egr valve. SOme are like that. IN my case the there is nothing on top of the EGR valve. Everywhere I looked at first, that doggone position sensor in right on top of the egr valve with the electrical plugin on top. And of ocurse that made sense mecahnically. I mean if the position sensor were on the firewall how could that work mechanically - right ??? So I was stumped bigtime.

MIESK5 below has a good pic of my egr with the position sensor sitting next to it, not on top. It is excatly like mine.

thanks for your help.

yo! good research!

here is some more;

P0401 Possible causes:

Fault in vacuum supply to EGR vacuum regulator solenoid.

Damaged D.P.F. EGR sensor.

EGR valve stuck closed or iced.

EGR valve diaphragm leaks.

EGR valve or flow path restricted.

EGR vacuum hose off, plugged or leaks.

VPWR circuit open to EGR Vacuum Regulator solenoid.

EVR circuit to PCM open.

EVR circuit to PCM shorted to PWR.

Differential Pressure Feedback EGR (D.P.F. EGR) sensor pressure hoses both connected improperly.

D.P.F. EGR sensor pressure hoses reversed.

D.P.F. EGR sensor VREF circuit open.

Downstream pressure hose off.

Downstream pressure hose plugged.

Damaged orifice tube assembly.

Damaged EGR Vacuum Regulator solenoid.

Damaged PCM.

had same code in our 96 2 yrs ago and it was the DFPE

EGR Service Tips, Ford by SMP at smpcorp.com via web.archive.org

http://web.archive.org/web/20040610225422/...view/tt2q00.pdf

EGR Valve Position (DFPE) Sensor Operation & Testing, Ford by Tomco Inc. tomco-inc.com

http://www.tomco-inc.com/Tech_Tips/ttt19.pdf

btw, Tomco makes an EGR Tube Screen for 84-96, neat stuff! http://www.tomco-inc.com/Catalog/m1667t.pdf

one more thAng that will go the way of rust soon is the EGR Tube

for 84-96 Bronco & Fords PCI, Inc http://www.pciinc.com/index.cfm

can buy locally or direct

and the check valve rusts out as well, PCI has them incl AAP, AZ, etc.

Thanks Miesk5. I found this same info with the two pics on another site and it set me straight. It was a relief to find a pic that looked like truck with the position sensor next to the EGR valve instead of the right on top of it. SO now I am just waiting for autozone to get me my position sensor and I can swap it out. Should be easy ?????? Thanks a lot for the info.

 

[nulife48]

Last year I replaced the DPFE, ran great no problems.

Here it is February 2007 and the trouble light came on....again....after being dormant for a few months anyway. COdes are P0401 and P0402, too much recirculation gas and too little. How can that be??? Well, I am just ignoring it. I got a piece of black tape over the light. THe valve cost me $60 or $70, can't remember now. Maybe in a couple years if I get the same trouble codes I might just replace the valve and than have no trouble light come on for a few months, or I may not.

I have a 1996 Ford Bronco, 5L (302), auto transmission, with 123k miles. I got a "check engine" light display one day. Took it to Checkers and had it tested. Code was P0401, for insufficient recirculated gas. I got a new EGR valve which included the gasket and two "washers" which act to restrict the flow into the EGR valve. They are slightly different size. Each had a different number stamped into it which I assume was cross sectional area of hole in the washer. I removed the old EGR valve and noticed there was no "washer" installed betw the tube and the EGR valve, so I did not install either of the washers provided. 3 minutes later I got the valve installed, engine running real nice and thought my problems were over. Not so fast. After 30 or 40 miles the check engine light came on again. No sweat - I had it tested and it was a P0402, too much recirculated gas. Hm....I installed the smaller of the two washers. Miles later same check engine light came on - but this time it was a P0401 - insufficient recirculated gas. So here I am laughing and wondering to do next. Now each time I touched the EGR valve, I disconnected the battery for safety adn to clear the memory. Also my EGR valve does not have the position sensor attached to the top of it, it is located in some as yet unknown place.
I ordered a new EGR valve position sensor from Autozone, but I need some help here. Where the heck is it? I looked everywhere, but can't find it. Hopefully it is not betw the rear of the engine and the firewall. It appears to be about 2 inches tall, black plastic, a plug for the electrical connection and at least one connection for a hose - maybe vacuum line??? Dealer charges $128 and I paid $23 plus ship/tax, so I am in the right price range.

2nd question is if I can get that sensor installed and the light comes on again, too little or too much recir gas, any ideas what to replace next ? EGR pressure sensor maybe???

The truck runs real nice now, mileage went up 2 maybe 3 mpg. If light comes on, I might just ingore it with some black tape. Bad idea?

Thanks in advance for your help. YOu guys provided some good info the last time.

 

[miesk5]

Last year I replaced the DPFE, ran great no problems.
Here it is February 2007 and the trouble light came on....again....after being dormant for a few months anyway. COdes are P0401 and P0402, too much recirculation gas and too little. How can that be??? Well, I am just ignoring it. I got a piece of black tape over the light. THe valve cost me $60 or $70, can't remember now. Maybe in a couple years if I get the same trouble codes I might just replace the valve and than have no trouble light come on for a few months, or I may not.

ok

The possible causes are another bad DPFE sensor, a bad EGR Vacuum Regulator Solenoid (EVR) or possibly a bad PCM (most likely wiring near sensor/solenoid). The first thing to check is the wiring for breaks and be sure the connectors are clean and tight. Also check the vacuum lines for proper routing and that there are no breaks or cracks in them

GL!