Evening All! We own a '99 141k mile 2.5 Tdi Avant Quattro. Recently it had started cutting out right after starting and then the central locking failed (probably unrelated). Then on its way back from a 140k service at our local specialist it broke down having cut out at a cross roads and has failed to start since. After suggesting the tank fuel pump, fitting a new one and the car no longer starting. My mechanic now "thinks" it's the fuel injector pump because no fuel is being "sucked" from the tank when the engine is being turned over. Since this is a £1000 part I'm a tad apprehensive to just go.. yeah slap a new one on! Soooo audi experts could it be the fuel injector pump? What is the tank pump supposed to be doing? I thought that was the low pressure pump making sure that there was sufficient fuel engine side.... Anyway a few questions I'd be really glad for your help; Is the immobilser attached to either of the fuel pumps? Can I isolate the problem to the fuel injector pump? How can I tell if the tank pump is working okay? I hear about a fuel pump relay.. could that be the problem? I'd be really grateful if anyone could help! Many thanks in advance!!!