90 4.9 300, code koeo 31. I've been messing with the sensor, swapped with another one, checked voltage, etc. What I have figured out is that the voltage is low, about .14 and it should be about .24v with no vaccum and 4v where it should be 5v at full vaccum. Now if I apply a little bit of vaccum to the egr, I can get the voltage in spec and the code will go away which is telling me that the plunger on the sensor isn't touching the egr when it is closed. Both the egr and sensor are new about a year ago from Amazon (I know, they are cheap and usually cause issues). So a few questions, since I ordered from Amazon sometimes they will say that a 5.0 part is the same as a 4.9 part so I'm wondering if maybe my egr valve is ment for a 5.0. Are they interchangeable or are they different? Is the clearance from the sensor different? Same with the egr position sensor, is it interchangeable with the 5.0 to 4.9? Just wondering if I just got wrong or bad parts. Then my follow up question is could I put something on the end of the plunger on the sensor to make it longer to where it would read correctly, you know what I mean? Thanks for insight, I'd rather not throw parts at it until I know what the problem is

 

I think I figured out my problem. I looked back at the egr I bought on Amazon and there were some reviews saying that the diaphragm is too short to reach the sensor properly. So it is the egr. Now could I shim something up in there to make it work or should I just buy a new one?

 

Most of the time we see aftermarket EVP sensors with the shaft too long to work on factory EGR valves. In those cases you have the option to shorten it. Since yours is too short, I would return it then find a Ford/Motorcraft version or a higher quality aftermarket. I believe the EVP sensor is the same for the 4.9/5.0/5.8L engines.

 

I sure would just go get a good used one from a junkyard, they last about forever in most cases
**** poor parts sure do suck

 

Correct, I just replaced my EVP (I still have the receipt from the PO, so not an old part) with one from a junkyard truck. It removed the codes plaguing me since I got the truck.

 

Correct, all those EVP's are the same. Only difference that I am aware of is the black and white ones are NOT the same and will cause a light if swapped