Ecm won't do self test after battery went dead driven 300 miles still no test for egr and cat

this is all history now, old OBD1 1993 car from ford
your post , i see you read thing about 1996 cars, OBD2
they are not the same at all, and OBD2 is USA invention and EPA mandated year 1996 up. by law here. and invention.

OBD1 , is way way more simple.
in fact super DDUMBB ECU. sorry no misfire codes ever. here.
it mostly only reports, shorted sensors, or dead open (as in wires cut)
and ours reports (USA) EGR failures too, weak. (NOX fails)
yes all cars need to be run fast and slow and be fully hot before the inspection, not just after any battery power reset.
do not reset OBD1 and get any smog tests, this is \wrong.
the CAT needs to be hot too and the engine
and the coolant fully hot , 180F or higher.
the ECU does have crude fuel trim mode. YES.
it does way batter, driving for 1 hour to get the LTFT long term fuel trim , learned. that is it only is learning by O2 sensors readings.
the 02 must be good, or engine will be rich with HC and or CO
the exhaust pipe must not be cracked near the 02 sensor or the engine goes rich,
there is no tricks here, OBD1 is well known here FORD for say 1985 to 1995, all early ECU injected engine them have ODB1, and is only fords version not like any other car on earth ever.
yes dirty engine can be hidden by a strong, CAT.
just drive the car , be happy it runs, most do not this old..
The next smog test may fail and if does worry then.
the car has check engine lamp, if out , be happy.
my guess is 1 of 2 things
1: cat weak, engine burns good
2: cat good but engine is bad , cat can not eat up the HC or CO.
in pro grade shop with a 4/5 gas analyzer
we can tap the from exhaust header
and do gas checks on front of cat and rear,.
this is the ACID test, and proves 2 things
cat good or weak.
or
engine is way too rich and cat is overwhelmed.

we can also trick the ECM in to telling us if the ECM is holding
closed loop at hot idle and at 25mph easy cruise.
if that fails ,the CAT will have short life span.
OBD1 , scan tools for ford are NOT easy to source, not sold in OTC stores, like NAPA etc.


NO not longer than an hour, no..
NO. and stop reading 1billion posts on OBD2, (and win)

your car is FORD OBD1, a horse of a totally different color.
join and old ford forum for old old fords
we are not them.
like here

https://www.fordforums.com/

not told is on rear wheel roller test and at what speed it failed.
most in USA if at all do 2speeds, did both fail NOX.
no report posted, as other gasses matter too.

in what country tests cars this old?? oddly
all engines make nox happens under high load. and too lean.
the EGR systems remove it the 1st half of NOX.
then NEXT the 3 way cat ,gets the rest ( a 1,2 punch it's out)
that shows how it works, end to end. Your EGR is failing.

The EGR path is not simple at all for sure 1986 , is horror. in fact.
later years went to electric motor drive EGR mains. but can fail like this let me say how. (carbon backed on them all can happen)

Do a EGR stall tests if that fails the main EGR path is blocked. full of carbon.
a good USA ASE shop can find this seems to me the 86' scares the young tech (confused) is par, many techs were in 1st grade then.
Us old guys seen all this and lived the horrors of 80s EGR jive
complex and loves to pack up full of carbon.

that year that engines there were 5 (wow) EGR systems used then.
the service manual show that fact, some cars I call slicks where sold to Pacific islands then , no EGR at all. yes. CALLED JDM. versions.
Learn that EGR Is smog and the rules to control it are different in 25 countries, or more. not told you is bad. nor where car was first told to.
I now go broad band, a 5 country list if fixes.
from simple to complex USA FED. USA calif , Canada and more.
see/????????? we can not read your vin or hood sticker that declares which of the 5 it is. at all but you? count the parts there for EGR and tell me and I tell you what it is.

there are 2 sides of this system (exh & vac) besides the CAT.!
the dirty packed up exhaust path end to and
and the controls side seen below. failed.

failures on control side are: ( or none at all on JDM cars)
1: engine never reaches, 180F temp( thermostat bad or missing)
2: speedometer dead, EGR only works rolling tires on some.
3: EGR is dead if at idle so if idle fails so does EGR.(idle switch bad?)
4: EGR is off line WOT, wide open throttle. too but no a problem here
so what can fail?
well I test the EGR main first, I use a tool called a hand vacuum pump that all techs have, every one,
and I pump the main (valve) down to 7 inches HG. and the engine stalls or goes from 800 RPM hot to 400 and shakes hard and or stalls, if yes GOOD !
this test is first for me, if exhaust side is blocked up it will never ever work, at all.
ok that test passes.STALL TEST. passed , time to move on.
tests, for vacuum are next
the vac port marked vac in red is ported vacuum.
I make sure it sucks are (vac)_ off idle (by my hand on throttle of carb.
if good there. the 50F BVSV valve passes vacuum to the next point.
then comes (worst case) the EGR Modulator.
the modulator has what I call a larger rubber bark tube,.
I pull this tube start the engine and the tube barks exhaust to my hand felt and heard., ok that is good if not the path there is carbon blocked, and must be fixed now. (even 10 new modulators is no fix)

last this the vacuum pulses at the modulator output end must reach main. (a vacuum gauge works here to test it) under throttle 2000 rpm
a vacuum must be there, or main will be dead.
The modulator uses CAT back pressure to sense engine load.
and the more load the more eGR flows and only off idle.
I test it at 2000 to 2500 rpm,. here. and now.

if there is a electric VSV valve here this path too can fail. ask.
that is all, I lived all this back then, so never forget it .
In fact never seen one of these cars not failing ever, until I fixed it.
they are very hard to fix. (you/me covered in a blanket of carbon)
even had to remove all manifolds and rod out all egr paths of carbon.
at cruise the EGR main must flow EGR exhaust or it is failing.

The system has to see a wide range of conditions before a smog test can be done. On most brands you have to drive at least 50 miles, at various speeds including stop and go, let it idle for 5 - 10 minutes, and run at freeway speed for at least 25 miles. It also has to reach normal operating temp of 195 degrees.

if you are failing emmissions test your evaporator canister is expired replace it and then you and your car will get a green light

How many miles since the failure to pass ?

The gas may be old I would put some Lucas in the tank and run it good.

Follow this drive cycle to reset the monitor.

http://www.obdii.com/drivecycleford.html

NOX is produced when cylinder temperatures exceed 2500 deg. The systems in place to reduce NOX are EGR and the catalytic converter.
If the number is only slightly higher than avg then I would suggest the EGR, make sure that any vacuum lines are attached and that the diaphragm moves freely, be sure not to damage the rubber inside the EGR.
Retake smog test, if numbers still out of range replace the cat.

Try running a tank of Supreme gas & a can of SEAFOAM in the gas tank. It might clear up your problem????? Go chance of it.

It could take more driving always make sure you have between 1/4 -3/4 tank or monitors cant run has anyone checked to make sure the EGR is functioning? Not just the valve but the EGR system?