Hi All i have lost combustion on no.5 cyl. (See drag car link in sig)   I have a good spark, Have swapped coil packs etc etc. It has to be a "No fuel fault" I have just wired in a resistor pack and am running New 1200cc Prescision injectors.   I have succesfully continuity checked my wiring from injector + to each plug on resistor pack.   From ian C   "One wire is a 12v feed that has already run through the resistor pack, the other wire is switched to ground by the ECU to open the injector.