That is an interesting one. The only thing that could even be remotely possible is if the wiring you disconnected somehow was damaged, and that is a long shot.
You listed this as a Chevrolet Caprice and in your post said it's a suburban. I'm looking at suburban schematics. I guess the first thing to check (if you replaced both pumps) is to make sure the two wires to the pumps weren't switched.
I attached two pics below. The red wire is for the front pump and the green is for the rear.
Confirm they are positioned correctly.
Let me know,
Images (Click to enlarge)
Saturday, October 17th, 2020 AT 8:28 PM