Sheesh this much money and no

HC absorber on the three way catalytic converter. That ought to raise the cold car emissions. Finally jacked it up and had a look.

 

HC absorber

yes it was on the Classic and was used to capture the unburnt Hydro Carbons until the catalytic converter got up to temp and then introduced them into the converter. Think of it as a blanket of activated charcoal wrapped around the shell of the cat and the mouth of the converter has a valve that closes almost completely to divert the exhaust into the absorber and the HC is absorbed by the charcoal and when the cat gets going the O2 sensor tells the main computer to open the valve and when it does the exhaust entering the cat provides a slight negative pressue on the absorber and it releases the HC into the main stream of exhaust going into the cat. Does that make sense?

 

I think it is

probably due to the flush of warm coolant that is stored in the "thermos" that is pumped into the cylinder head and that helps with the lowering of HC as compared to a true cold start.

 

Not the cat but

thru the water jacket in the cylinder head. As the external temp of the cat is problaby in the order of a thousand degrees F. when it's at operating temp, it would evaporate the coolant almost instantly.