I got a 89 lx 5.0 which should pass german inspection stock though I have to much oxygen comming out of my exhaust. The co2 and nox and all is normal. My o2 sensors are functioning properly. I changed my egr valve. Does anyone have any imput on a solution??

 

Ther may be an exhaust leak that you can't hear that is introducing o2 in the system and the sniffer is picking it up.

 

I got a new cat back magnaflow exhaust. where you saying before a leak before the cats?

 

The car has been gararaged for nearly 12 years now unregistered. Do you think The I think it might be the cat converters. I don't know what you ment when you said sniffer?