Yes Duke the TX testing procedure is called an ASM-2 (performed on '95 and older cars, OBDII on '96 and newer) -- I suppose identical to the CA test.

I just phoned the testing facility about the high O2 readings and he told me that the value is taken from the ambient air, not at the tailpipe.

So that explains it. I asked him why and he didn't know and he referred me to the Texas DPS.

Time to take a look at the EGR valve.

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-Paul-
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi