Car wont start after a sudden shut off
 

Ive got a 2001 2.7t a6 and over the last couple of months my car has a progressively harder time starting. Sometimes I have to crank it 4-5 seconds before it will start and if it doesnt I would turn the key off and try again and it would start up immediately. After it does it idles rough for a couple seconds then levels out. Ive ran premium and fuel system cleaner through and it didnt get any better. Then yesterday i went through the same starting process as before...walked away for a couple of minutes and in that little time the engine had turned off and now it wont turn over at all just cranks and cranks. Ive taken my seat out to get to my fuel pump and when I turn the key to the on position I can hear it click but thats about it no pumping what so ever. I also pulled off the rubber tube off the output and i get no flow when i turn the key to the on position. Ive taken my dash apart to get to the relay. I can hear it click when i turn the key to on position and then click again when i turn the key off. Im not quite sure how the relay works but i always get a constant 12v on 3 of the five pins and the other 2 always remain at 0. Ive also tested the plug at the pump and i never get power to it when I turn the key to the on position. Not quite sure what I should start replacing right now. Does this sound like a relay problems or not. Ive run out of ideas for now.

Thanks for reading!

Check the battery with a load tester, it may be the problem. If the battery is good, change out the relay. This will be a good start.

Can relays gradually go bad (since my problem has been going on for a little while now) or do they just suddenly go bad?

They can do either, gradual is more usual but often goes unnoticed. Teh relay contacts just get resistive due to build up of oxidized contact material. Sometimes the coil fails usually when it's hot due to wire insulation failure and gradually gets worse and worse.

When was the last time you replaced fuel filter? Clean or replace ERG valve? Auto Zone will check and clear code for you.