My car ('94 BMW) failed the low speed NO test. I was told the CAT was
wearing out. I was allowed to drive around the block to heat it up, and it
was immediately retested. It passed the retest, and the numbers were
significantly different.

If they told you your CAT is faililng, I would be inclined to believe them.




"Mike M" > wrote in message
.. .
> My son's 89 6 cyl.Cherokee just barely failed the Ca. smog test. It
> passed the 15 MPH but failed at 25 MPH on the "NO(PPM)" part of the test
> (max allowed is 875 PPM.his read 1066 PPM). Anyone have any ideas what
> the problem might be?
> The mechanic told him it is probably either the O2 sensor or the
> catalytic converter.
> TIA
> --
> "Trust me, I do this all the time"
> Mike M
>