Smog test

Which code(s) are staying in the system and what repairs relating to those codes have been completed?

I misspoke in the original post. The van sat for a couple years. I charged the battery put a fresh tank of premium in it and it fired right up and ran great.No check engine light or anything . Drove it 30 minutes to get it warm and drove to a CA smog station. I did not realize that that tIt has done various error codes in various ways he OBD had not run the 4 tests that get run by driving your vehicle in ridiculous ways The CO2 HC and all other readings were well within parameters. But the OBD was not ready, so the vehicle did not pass. after driving it several hundred miles to make the OBD ready. I could not get the CAt Mon to clear. I checked vacuum hoses for leaks, replaced the EGR valve, DPFE,checked to make both were functioning--- proper voltage on DPFE..applied vacuum to the EGR, vehicle sputtered. What it is doing now about 3 times in a row is getting down to EGR and CAT MONITOR tests. and then when it gets down to EGR code the check engine light come on and I repeat the process. The van was payment for some work I performed for someone. I don't believe they knew of the issues with the vehicle. But I am about to call a junk yard and it made me mad because it was the first year of OBD 2 tech. The PCM is 23 years old. I don't have a phone, TV, or pair of pants that old. I have done my due diligence the readings are within range and I give.Magic cure would be appreciated or a smog Place near SF that understands.

No problem. Could you give me the codes that are stored, both active and pending if possible. Setting that long it could be a plugged EGR passage or something similar. The code(s) that are stored might point toward a better cause. Some codes can set and they block everything from running. It sounds like this could be a two trip code. It will run once and be stored as a pending, the next time it runs the test turns on the light. So you repair one thing and the light goes out, only to come back when the blocked test runs.

The latest one has been catalist monitor and P1409- EGR solenoid.

P1409 is a circuit code. It means that the PCM isn't seeing the voltage it wants to see from the EGR vacuum regulator valve based on how far it is commanding the EGR to open or close. The terminals on them are prone to corrosion.

The EVR is a solenoid valve as in the image below. It should have a Red wire and a Brown wire with a Pink stripe on it. Disconnect it and use an OHM meter to check between the two terminals. You should get between 26 and 40 ohms. If that is in spec, measure the voltage on the Red wire, it should be battery voltage. The Brown/Pink wire is the control wire, It goes directly to the PCM at pin number 47. I would measure from the connector to that pin with the ohm meter as well, for that one you want less than an ohm if the wire and connector are good. If those test good it could be the driver transistor for that solenoid failed, however I suspect corrosion at a connector as it has been setting.

Thank you for taking the time and energy to respond. I apologize for not giving you all the information in the first question, it's just I've told four or five people ask as to what's going on with it and none have had a magic bullet.I forgot to mention it also was taken to a shop after it didn't pass the first smog test.After it failed at the test only smog place my brother said to take it to his mechanic who had it for 12 days and through their hands up in the air. I was sorta glad it wasn't something simple that I missed, but I hope my brother didn't pay too much of a bill they did put a couple hundred miles on it trying to do the drive cycles but to give it back without fixing it it sucks I don't know my brother had me some money so he took care of the bill but I don't think I would have paid him very much. Again thanks for the technical expertise.

Not a problem, it's what we are here to do. Try to help people repair their vehicles. Trust me, I have had vehicles that really made me want to pour on some gas and toss a match inside as I walked away.