Trying to SMOG but EGR is not cooperating

Hey all.
So I'm trying to smog my 1990 XJ so that I can register it and the EGR system is not cooperating. The EGR valve itself is working but the EGR solenoid is not for some reason.
I went to picknpull and grabbed 4 more solenoids and same thing. I have positive and negative to the solenoid. Could it be that I have 5 total bad solenoids? Is there any other thing that could cause the solenoid to not function properly? Thanks for any help!

P.S. I know that they don't work at idle so in the testing, I made sure that I was modulating the throttle...

Did you test the solenoid independently? Putting 12VDC to the terminals (they should not be polarised) will give you a "click" you can feel, and applied vacuum should be released.

You may have a wiring fault which prevents the EGR solenoid from being tripped by the ECU - in which case, replacing the solenoid will do nothing.

Nine times out of ten, a sensor fault or an actuator fault will be the sensor or the actuator. However, because of that one time out of ten, you should never just assume that it is the sensor or actuator - because it may not be after all. Test before replacement.

Just a theory I've never tried it. But the default for the solenoid is open to vacuum with no ground. The ECU grounds the solenoid which closes the solenoid and cuts *off* vacuum. Just the opposite of what you'd think. No electrical connection and the EGR is always under vacuum. Unless the tubing or transducer is plugged up. I did have one transducer go bad, it was full of dust, mud or whatever.

Pull the plug, if the motor idles down and acts funny. the vacuum supply and EGR are likely in order. If it doesn't idle down, you either have no power to the solenoid, you have an open ground circuit (wire or connector) or the ECU isn't grounding the solenoid.

My egr vac solenoid doesnt work, I do not have to smog my heep anymore tho. Runs great without the aweful egr functioning. Hopefully, swapping in a GM V8 tho.

Amplifying above, be aware that the egr system is designed to shut down during idle and acceleration, and only to open the valve while cruising. It may be hard to test because of this.

There were two different EGR systems used, one I think just for part of 1987. The first has a single valve, and the second a valve and a separate modulator. I'm not entirely sure what the conditions were for the second type, but the first type also was designed to leak vacuum until there was a certain level of exhaust back pressure. Because of this, a good valve would always flunk a vacuum test. I think the second type also requires back pressure to the modulator, but I can't remember it all now. It's been a long time.

Make sure there isn't some little vacuum leak somewhere, and that the vacuum hoses are connected right.