Hello new member here. Just bought 05 2l a4 with blb engine I filled up car with petrol unknown, drove it for 100km kaput. Had to change fuel pump went breakers route then injectors. Injectors were refurbished old injectors started car but there was a loud knocking sound, new injectors put in car would not start. Sent them to be tested they were perfect. INJ num 0414720404. Can anyone give reasons why car might not start ? I thought these inj. should drop in no programming needed. Car has been garaged for going on 7 weeks alot of money spent and still no joy. Any feedback would be great.