yo, I am dwelling on the DPFE and its hoses right now;
it is mounted on passenger side, high, next to throttle body and in front of intake manifold; just above alternator; - MIESK5 NOTE: only 95 5.8L California models & all 96 have the DPFE Sensor instead of EGR Valve Position Sensor (EVP)
Location pic in a 96 5.8
Source: by bergs at SuperMotors.net
The DPFE Sensor measures EGR flow across an orifice located inside the special EGR Tube (CHECK TUBE FOR CRACKS, etc.).
The orifice is positioned between two hose ports coming off the tube which are connected to the DPFE sensor with special heat-resistant hoses. When the EGR Valve is open, a pressure differential is created across the orifice (intake manifold pressure vs. exhaust pressure). By design, this difference in pressure is measured by the DPFE sensor in terms of voltage. The DPFE voltage signal output to the PCM is directly proportional to the flow of exhaust gas entering the intake manifold.
The PCM determines optimal conditions for EGR flow and then, based on the DPFE voltage signal and some other sensor data, activates the EVR to open and close the EGR valve as necessary.
The EVR is a solenoid with two vacuum ports. One port is connected to a vacuum source/supply, and the other is connected to the EGR valve. There is also a passage that vents vacuum to the atmosphere.
A disc inside the solenoid is moved by electro-magnetic force, as directed by the PCM. If more EGR flow is required, the PCM increases the duty-cycle to the EVR, moving the disc to close off the atmospheric vent, which in turn increases the amount of vacuum flow to the EGR valve. If less EGR flow is desired, the PCM decreases the duty-cycle to the EVR, allowing for more atmospheric venting and hence less vacuum flow to the EGR valve.
The EVR is a "normally closed" solenoid, which means that when it is de-energized, the position of the disc allows for maximum venting to the atmosphere (resulting in negligible vacuum flow to the EGR valve).
Note that Ford EGR systems DO NOT engage when:
The engine is cold ;
The engine is at idle;
The engine is at WOT;
At low ambient temps (water vapor from the exhaust can freeze on the throttle plate).
Testing, Vacuum/Voltage Parameters & pics on both older Aluminum & Newer Plastic Version
Source: by rockledge.home.comcast.net http://rockledge.home.comcast.net/~r...tage-Test.html
To Test EGR valve, and other parts go to my EGR section @ http://www.broncolinks.com/index.php?index=146