sorry I didn't get the info for you, my home computer went haywire, and never got to my book. hopefully tonight.

 

thanks again!

 

I put a picture in my gallery under my bronc that shows the connector for the EVP sensor
the latest year I have the wire collors for is a 93, but here they are
EVP signal == Brown/light green
Vref = brown/white
Sig rtn == grey/red

to test if it is bad
w/ key off, disconnect sensor harness, turn key on and measure the voltage between Vref and Sig rtn, it should read between 4 -6 volts. If it's not check the wiring. this is unlikely but it does happen.
Next turn the key off and connect an ohmeter to the EVP signal and to Vref, disconnect vacuum and connect a vacuum pump. As you increase vacuum the reading on the ohmeter should go from around 5500 ohms to 100 ohms @ full vacuum. If the EGR valve doesn't hold vacuum you have a bad EGR valve. If the resistance isn't in the range then the EVP is bad.
If you don't have a vacuum pump just undo the sensor from the housing and push the rod that sticks out the bottom to make sure that the sensor opperates in range. If it does not operate in range then the sensor is bad. other wise your EGR valve itself is bad.

Hope that helps, let us know how it goes.

 

Guys, I don't have a vac pump. I still don't know what my egr valve looks like or my valve position sensor. Maybe I need a haynes manual?

 

Yes you need a Haynes manual. Anyone who plans to turn a wrench on their vehicle should get one.

Your EGR is on your intake manifold, on the passenger side just behind the Throttle body and is held on by two bolts. There are photos in my gallery from my Throttle Body upgrade project that show a newly replaced EGR. There are more/better photos on my website.

At some point they (ford) got away from using the EGR position sensor, not sure if it was gone by 95. I have a 96 5.0 and the EGR position sensor is no longer used.

My 86 5.0L EGR was in the same location, but included the position sensor on top of the valve.

Hope this was helpful, if not, give a yell and I will try to provide more info.

Tom H.

 

The EGR is normally closed at idle. There shoould be no vaccum present at the EGR at idle, If you pull the hose off the EGR and the engine runs better , there must be vaccum present at the EGR. This can be confirmed by pulling the hose off at idle to see if the engine runs better then check the hose to see if there is suction there. If there is the EVR is at fault. It can be taken apart carefully, and cleaned. I had a bit of grit stuch in the rubber coated steel disk at the bottom of the EVR which caused the valve to stay open and provide a bit of vaccum to the EGR at idle causing it to idle roughly.

 

When you say evr, are you talking about the sensor that is on top of my egr valve? I have located my egr and I am going to take the sensor off and the egr and clean the hole where it goes in to my intake.

 

If it runs better with the vacuum line off, the egr is not the problem. If it was leaking, it would run the same either way. The evr(egr vacuum regulator) is connected to engine vacuum, it opens allowing vacuum to the egr. It then cuts off vacuum sealing the vacuum to the egr once the desired egr opening is detected by the evp(egr valve position sensor). The evr has a bypass valve that releases vacuum to the egr when the comp says so. The evr is an electrically controlled vacuum solenoid that regulates the vacuun on the egr. It sounds like the evp is passing vacuum to the egr when it is not suppose to. Probably bad evp. Haynes manual explains all this and provides troubleshooting order for it.
Here are pics of a 1990f150 302


BroncoBasher

 

As stevieray said, you may want to clean the evr.

 

Man those pictures are a great help! Thanks a lot! Tomorrow I am going to clean my evr and probably buy a evp because its only about $30.00. I hope that this will help with my gas milage. There is no telling how long this has went on with my truck and I hope it has not hurt nothing. I need this truck to last two more years since I am recently in a new job with little pay but lots of potential!(That oil pump cost me $550.00 to have installed) It has 150,000 miles on it and I was wondering what else I might do to make this truck last longer. Maybe some radaitor flush or maybe yall have some more ideas.

 

I replaced the valve position sensor but in the process I broke the vac line going to my egr valve. Should I replace the complete line, and will it hurt to drive the truck untill I can fix it tomorrow.

 

Unplug the wiring harness from the EVR and you are ok to drive it. As for replacing the complete line, it depends on how brittle it is. I broke mine and I just patched it w/ some vacuum hose that fit over the old one.

 

I got it fixed. Runs like a champ! Thanks Guys