Emission control

[David's Plus]

I went to the inspection station today and i failed for emissions. MY NOx was way off, standard is 970 and the reading was 1499. The guy at the inspection station said to check my oxygen sensor, but that would not be the cause of the problem that mean the oxygen sensor isn't reading and it would not show on the check engine light.Why is my NOx up so high? Does any one know?
thanks

PS
the guy that did the inspection ran the car on the dyno as a 3.8 ford not a 3.0 yamaha?? does that make a difference. I live in New Jersey. I don't know if emissions are standard on all cars or not. I have a 91 plus

 

[naval-avi8or]

I went to the inspection station today and i failed for emissions. MY NOx was way off, standard is 970 and the reading was 1499. The guy at the inspection station said to check my oxygen sensor, but that would not be the cause of the problem that mean the oxygen sensor isn't reading and it would not show on the check engine light.Why is my NOx up so high? Does any one know?
thanks

PS
the guy that did the inspection ran the car on the dyno as a 3.8 ford not a 3.0 yamaha?? does that make a difference. I live in New Jersey. I don't know if emissions are standard on all cars or not. I have a 91 plus

Yes that could make a difference. When my Nox was bad in CA it was because both my cats where shot.

 

[MADDOG11]

Yes that could make a difference. When my Nox was bad in CA it was because both my cats where shot.

You hit the nail on the head! Most likely your cat's are fried! Change them out and take it for a retest to start.