thanks for the reply. ive not tested the signal as im unsure what wires to be probbing. the youtube vid is good i,ll try probbing the wireing as it exits the ecu with my test light. even after read the wireing diagram im unsure. ive probed loads of stuff luckaly i only keep blowing fuses. acording to the vid my test light is the same as his it should simulate a noid lamp. ineed to compare the working supply from a good injector plug to the suspect one engine running. as im not a sparky the tests ive carried out are showing its an ecu driver problem but im not confindant enough in my findings ive ran up new wires to the injector from the ecu abandoning the original wireing.what ive replaced i keep in the boot spare apart from the new plugs. im trying to get a mobile sparky to come out to confirm my findings but they have a funny old way of working around here as they only asnwer there phones when they feel like it and have no answer phone message to say wether there dead or alive. ive got more spare fuses i,ll try what matey said in the vid. but really i need someone to test the ecu for me which is the next step after this thanks once again