EGR Vacuum Solenoid E77E-9D474-C1A 2.3l ford ranger 1985

[CDW]

What does this exactly do Im having no luck at auto parts houses to get a replacement they say its a dealer or junkyard item. So Im wondering what exactly this does and how the truck would act when it messes up. Im unable to give it much gas and its idle is rough and dies. Could this be causing it? I know it needs to be replaced its broke broke.

 

[RonD]

EGR valve has a vacuum hose attached to it, with engine idling remove this hose and put your finger over the end of the hose.
Do you feel a vacuum on this hose, is it sucking air in, it shouldn't be?

Does engine now idle better?
If so then yes your EGR solenoid may be bad.

Follow that vacuum hose back to EGR solenoid, it will have an electrical connector and another vacuum hose attached, that hose goes to intake manifold, it is the source of the vacuum pressure.
EGR solenoid opens and closes to pass that vacuum pressure to the EGR valve.

The EGR(exhaust gas recirculation) system helps reduce NOx emissions when engine is under a load.
NOx is generated when cylinders run hotter than normal, if exhaust gas is added to intake during this time cylinder combustion slows down so heat goes down, reducing NOx, it also reduces "pinging/knocking"

The computer controls the EGR solenoid, the electric connector.
When you are driving and open throttle, engine load increases and computer will start opening EGR solenoid to pass vacuum to EGR valve.
Computer pulses 12volts to EGR solenoid to open it a little or alot, so open EGR valve a little or alot.

But at idle there is no reason to use EGR solenoid or valve, so there should be no vacuum at the valve, if there is then exhaust gases coming in would foul up the idle.

 

[tomw]

The 85 with EFI has two solenoids under the plastic cover, passenger side rearward of the battery. One controls vacuum supply and the other 'holds' the vacuum set. The EGR valve has a resistor that the ECM uses to compute 'where' the EGR valve is set. The ECM will 'command' the EGR to move open or closed by adding vacuum or venting vacuum. Once set, as in for cruise, it will just keep the vacuum until it needs to be vented when you slow down below a set speed.
The supply solenoid will be enabled off idle, above some set speed & rpm. The hold solenoid will be energized to move the EGR via the diaphragm, and on command, vent the vacuum. More or less this is how it operates, but I may have flip flopped a function.
If you can find any solenoid valves, you can make them work as all they do is control vacuum on command from the ECM. One should have a sponge filter over the 'outlet' for dumping the vacuum to atmosphere. The filter is just a small cube of sponge.
The exact part numbers are only required for mounting to the bracket. You can likely find an equivalent on a lot of models.
If worst comes to worst, you can try LMC parts for an exact fit part. Be prepared with a full wallet.
Or, you can google for this phrase and get a lot of hits:

"1985 ford ranger EGR vacuum solenoid"

without the " marks at either end. Rock and O'Reilly show up near the top...
tom