Carpdad you are making this harder than it needs to be. To answer the main question, yes there is a problem with the ECM. Once the monitors are set to ready the only way they go back to not ready is by disconnecting the battery or resetting the ECM with a code reader.

If you just want to get through the emissions test, do the drive cycle and emission testing on the same day. The ECM needs to be removed and repaired.

 

Thank you for the reply. I will look into replacing the ecm. Why me!
NJ and it turns out i can pass with 2 "not ready" for 1996 car. That does gives me time at least.

 

No, there's nothing wrong with the EEC. You just don't understand what "not ready" means.

The EEC can only manage the system correctly when it's in closed-loop, AND it has learned the baseline adaptions for the sensors. You've gotten it to store the adaptions in KAM; but EVERY time you let it cool down, it will no longer be able to read the HEGOs. So it will be "not ready" (open loop) until they heat up.

Stop fussing, and just drive. NOTHING that the scanner tells you is a "symptom" of any problem - it's just information to help you diagnose some symptoms. If you're NOT observing any symptoms, you DON'T need to keep fussing with the scanner. Put it down, and drive the truck. Wash the engine & undercarriage regularly, and follow the maintenance schedule religiously.

 

Thanks for the reply. I did get the green light (all ready) twice on my obd2 reader. Both times, I tried to follow the ford cycle instruction as closely as possible, including stops, idles, steady 60 and variable 40-60. Repeat but I got all ready green light twice. But each time, after several minutes of car turned off, all those not readys come back.
I am asking here and there. Couple of posters suggested checking the electricals that are always on even after key is off and removed. There is a fuse for this? Just got these info so I will check them. I also plan to go back to your diagram of the ecm harness pins and see what I can figure out. Sure would appreciate if you will guide me step by step, but I think this is about the last thing I can learn/check before deciding ecm replacement is necessary. I just didn't want to replace the part before try to check the harness/other supporting parts for ecm.

HEGO (search says this is heated oxygen sensor?). I will do more driving above the ford instruction but how much more? After finishing the cycle instruction, I drove more to get home, etc, and even got the all ready lights. And if oxygen sensors are not monitoring well, shouldn't there be some DTC or MIL? Againk, thanks for staying with me about this. BTW, if oxygen sensors aren't getting heated, does it show up in the reader?

 

You're still not getting what I'm saying. NO VEHICLE is "ready" when it's cold. Not even the ones rolling off the assembly line & in the showrooms right now. "Not ready" does NOT mean "problem to be fixed". It certainly DOESN'T mean "replace the PCM". If you want my step-by-step guidance, here it is again:

1) PUT THE SCANNER AWAY.
2) Drive.

 

Inspection passed. Wanted to high 5 the last inspector and he shooed me away.
I changed the pcm. Rockauto and got the part number after removing the original. I still have egr not ready but nj passes with one not ready for 1996 car. Searched for other drive cycle instructions and one thing stands out: going to 60-65 then coasting to 20 or stop without braking. Using no brake at this time seems to be a key but haven't tried it. I also need to check the egr valve and the system if no brake thing doesn't work, but now I have the time. Slowing down to 20 without brakes, I need a highway and maybe at 5 am.
Before the new pcm, checked the pcm harness pin outs for kam and the grounds, and they all checked good.
Search for "hagerty.com" and for checking for voltage drop. Invalueable and clearly spelled how to check the grounds with a multimeter.
Finally deciding to change the pcm was based on my reader. All monitors were ready at the end of each drive cycle but my pcm didn't remember them. I was also getting codes that would go away on next drive cycle. I thought these behaviors were not like a computer and decided to change the big part instead of manually checking each part.

With new pcm: oxygen, heated oxygen, 2nd air - got ready quickly, just the beginning of thru town drive cycle. Catalyst also soon after. With old pcm, it took all town and highway (variable and steady 60) for all 5 emissions to show ready.

Thank you all for the help. Got me through all of this. Learned a lot, and hopefully, will remember them.

I did throw iac and pcv in, but didn't change anything. Oxygen sensors were changed before but left them as is. Other emission parts are 1996 original.

Almost forgot. About the pcm gasket. It doesn't look/feel it will be water tight now. Should I seal around the gasket? Does the pcm and the harness need better water seal? I was thinking something like electrician's putty or maybe some silicone, which should be easy enough to remove if necessary?

Old pcm had some rust and corrosion on the bottom side but didn't show any leaks/corrosions or severed paths.