I have a 110 td5 that turns over but doesn't start. Ran great previously but not today. Cannot hear the fuel pump priming, but it was replaced 2 years ago because it was antisocially noisy. Pulled off the return fuel pipe off the cooler and got no fuel. Sprayed engine start up the intake and it fired up briefly. Removed the pump relay and it metered ok. Bypassed the relay with wire and fuel flowed but still wouldn't start. Any ideas?