Fail results
asm2525
limit/reading/result
1689rpm
dilution 14.7
HC 62/60/pass
CO 0.35/0.24/pass
NO 700/1073/fail

idle
rpm 807
dilution 13.0
HC 200/47/pass
CO 1.00/0.14/pass
NO na

Update on what was done and what was found.

I replaced my catalytic converter (Bosal) and O2 sensor (bosch 13913). Entire exhaust+gaskets are brand new
I found and replaced a broken vac line at my fuel regulator (completely disconnected)was rubbing on my a/c hose. new hose
I replaced a broken ground braided wire (firewall to engine). New wire.
I re-fitted the flame trap housing. It seemed to be just sitting on top rather than seated. trap was clean.
Tested and tightened all duct and hoses after AMM. nothing loose.

Before the work the OBD test coded the popular 2-3-2 "fuel system compensating for lean/rich mixture at idle".

Now I get 1-1-1 Ok Before and after long test drive.

Thoughts, opinions.
My guess
The vac line should help HC
The O2 should help HC and CO
The cat should help my failed Nox.

I am actually optimistic

Do I have to reset the ECU? Details please.
--
91 240, 98 S90

change the oil, makes all the difference in the world, then air filter and fill'er up with hi-test gasoline. this actually worked for my just by changing the oil and burning premium gas. so that should be definite if it was running rich.

you might or might not want to check for a vacuum leak with a can of "starting fluid" (dimethyl ether), but that can be bad if you got a faulty ignition wires or loose battery connection i just hold the can back and wear glasses, the stuffs more volatile than anything but has no btu's just burns off "woooosh"

spray it around hoses, intake gaskets, injectors, wear glasses. if engine rpm increase, duh leak.

You'll pass.

i would reset the ecu-it's too easy. just pull the fuse. resetting means it WON'T have to relearn anything between now and the test, back to basic settings. before you restest, drive the car about 2 hours or so. this will cook off any fuel from the crankcase, which means high hc. good luck, chuck.