My 96 300tdi has been suffering with ocasional power loss, so in my wisdom i thought i would place an air line on the fuel pipe so i could maybe blow any blockage out of the way and into the tank after doing this i bled the system ???? and started the engine. all was fine at idle untill i tryed to rev the engine i had loads of smoke from the exhaust and engine was running real bad so cracked off injectors and tryed to re bleed this seemed to work for a while and then started to run bad with the smoke again. so again cracked off injectors this time smoke cleared and engine revved ok, you get the idea. So my question is has my fuel system suffered from just an air lock causeing the smoke and bad running or is it something else (i will do the sedimentor tomorrow) thanks guys