I have a 2005 audi a4 3.2 I replace the ecu and fuel pump but it won't start I'm also trying to find the fuel relay

SOURCE: won't start fuel pump replaced new tank and

Nephew had similar problem on different vehicle - had spark to plugs, limited gas, everthing else checked. I did one thing first - check for two fuel filters - one in the tank was only screens and one in the line itself. Found a little in line filter just outside of engine compartment under car next to frame that looked like it had never been changed - partially clogged - replaced it.Almost ran but would not keep running. I had rotor and cap pulled - found that the screw holding rotor in place was loose. The rotor edge next to plug wire leads was chopped up and the cap's plug wire leads were heavily oxidized. Replaced them and got it running but a little rough. Pulled the spark plugs and found gaps from 25 - 100 ---replaced the plugs with correct gapping and it ran really well.