just make sure you have a good earth from engine to coil and everywhere else check all the other wiring around the engine especially behind the throttle body area as the exhaust heat shield can burn them apart from that re check your relays not all parts that i've changed have been good parts thats from experience then you end up trying everything again

you will get there in the end mate always seems to be the 8v's ive had 3 and all had issues now have a 16v and not one problem electrically yet (touch wood )