I appreciate your additional input. The check valve is working fine, I've tested it several times and it always shuts off. It was replaced some time ago under warranty because the the weld broke on the connecting tube on the original. The whole thing was replaced as an assembly, the dealer told me at that time it was only available that way. So, hopefully, I already have the improved version. I reset the check engine light by disconnecting the battery and I'll see what happens. This is my wife's car and she worries when lights come on. I took your advice and ordered the electrical schematics which seemed reasonable because they will cover both of my cars (I also hsve a 1999 V70, no air pump thank GOD!) Thanks again.