So I'm still working on figuring this P0401 code out. Here's where I'm at so far: I found the following link: Part 6 -How To Test the GM EGR Valve -Buick, Chevy, Olds, Pontiac
I worked my way through all of them, and it passed everything with one small exception. The wire labeled "E" does have 12V, but only while the connector is disconnected. As soon as I plug it back into the EGR valve the power drops to ~0.03V. I'm stumped. There is no carbon blocking anything, and when I try to start it with the valve off it stalls immediately. All other tests are within limits.
Of course, to add insult to injury the brand new CV axle that I installed in February has a cracked boot and puked grease everywhere, so I'll have to do that damn thing again. I'm ready to sell this car.
