Ran across one of these this week. I had no previous knowledge of them. Wasn't fully convinced it was a GM project, but the AC Delco Variable Fuel Sensor made me look into it.

Metal, silk screened decal on the manifold;

Nothing of interest on the Emission Control Sticker, not even California emissions;

Different label on the fuel door;

No unique markings on the dash or instrument cluster.

The GM Service manual supplement is readily available;


Even found some info on emissions presented at an SAE conference;