Ken,

Thanks for the info. I bought the car used and the valve appears to be new, probably replaced in an attempt to correct the check engine light with a cheaper component than the pump. But I’m still looking for the best way to test the unit. Do know of a better way to test the valve?

I pulled the inlet hose and felt for escaping exhaust gas when the valve was energized and when it was off. It seems to seal completely when it is shut off. My original thoughts were to use an old style fuel pump/vacuum gage to check for minor leakage but with the success of placing my finger over the inlet I skipped the instrumentation. BTW with the engine at idle and the valve open I was surprised to find a slight vacuum on the inlet. I assume this is due to the placement of the air injection jets in the exhaust ports that a venturi action occurres at low exhaust pressures.

Charlie