No CEL...No fault code..???
 

300E 1990, per my tech shop:

My oxygen sensor is inop and catalytic conv is now toast, but I have no CE light (never have) and they're not getting any fault codes whatsoever...

How can this be?

To update my own post...Merry christmas to all, and to my old 300e!

Took the old girl to an old trusted tech, put in a new Ox sensor...and voila! Passed Ontario e-test with flying colors!
My HC went from twice allowable to perfect. No new Cat needed!

He thought it was weird I got no CEL but shrugged.

Here's a word to the wise...we both looked at the exhaust fumes this AM, and he was sure the engine was burning oil...he thought A LOT of oil. Time for valves and seals, he prepared me for.

But really it was lots of unburnt fuel...looked like coolant smoke but was just gas. I read that unburnt gas would be black, but this time it was just rich and white.

Im very happy!

Merry Christmas / Happy Hannukah / Blissful Kwanzaa and seasons greetings to all other fine folks on this fantastic site!!

Congratulations.
Btw., if you were burning a LOT of oil, your HC would be through the roof ( probably somewhere in the 1000's ). ;)

Thanks Manny..

Ill tell you a funny story...when it got tested in Sept. it failed the high (2500 rpm) test HC with a result of 94ppm vs limit 50ppm. This was from a real Drive Clean computer My new paper says 35ppm vs. limit 200: PASS at that high speed. All my old test result papers say 200 PPM at both idle and 2500rpm.

Was there ever a limit of 50 PMM in Ontario on my car?. Even my OLD results from '94, '92 etc say limit 200 pm at both idle and 2500rpm?

Either way, I needed a new O2 sensor. and it did it's job cept tell me with a CEL..

No. Even my 2000 has an HC limit of 150 ppm.
I think your test technician entered some wrong data. ;)
You may ask for a refund on the Sep. test.
Btw., Drive Clean sucks & is the biggest ripoff ever.