Wednesday I took my gas tank off and cleaned it out. Today I finally got to put it back on and when I went to start it, it ran for about 2 seconds and then died on me. Then I realized I had forgotten to plug the connection for the fuel level sending unit, so I went and plugged it back in. Now the car wont start at all. I disconnected the battery twice now to reset the ECU and that hasn't helped. My fuel pump is outside the tank so i never messed with it. I know fuel is making it all the way to the outlet on the fuel filter but I dont get any fuel on the return line at the tank. Anybody got any ideas on what could be wrong?