Emissions test

My son has a 1990 Century with a 3.3L engine that has failed our state's emissions test. We are currently doing the simple things like plugs, wires
and checking vacumn hoses. The OBD shows no registered errors of any kind. In checking things, I can't seem to find a EGR valve or a PCV valve. The Haynes manual mentions a digital EGR system for some models and after that the book is useless. Any ideas on EGR?

The PCV valve is there... close to the steering pump, above the water pump.
Unfortunately, there is no EGR valve on 3.3L.
It'd help if you could provide more info.
What your car failed: NOx, HC or CO?
If it was NOx (I suppose so, otherwise you wouldn't look for EGR) try this link: http://gatewaycleanair.com/mechanic/air4_4/dirtymaf.htm
and...
Good luck.

My son has a 1990 Century with a 3.3L engine that has failed our state's emissions test. We are currently doing the simple things like plugs, wires
and checking vacumn hoses. The OBD shows no registered errors of any kind. In checking things, I can't seem to find a EGR valve or a PCV valve. The Haynes manual mentions a digital EGR system for some models and after that the book is useless. Any ideas on EGR?

Thanks for the reply. Upon checking the state's form I see they don't count NOx in the test. What they do rate is the HC and CO. For HC the state wants .80gpm and it tested at 1.07gpm and for the CO its 15.0gpm and the car tested at 29.3gpm. I'm just checking as much as I can with the little knowledge and info that I have. Also not trying to quess at it. kink