Hey there, currently I'm having a misfire in cylinder 3.

My 2003 350z was running absolutely fine, took it out for a quick drive one day and let it sit for a few hours when I started it back up again it instantly started misfiring and the engine shut off while I was driving about 10 seconds down the road. The misfire then went away for a day and came back, now it is constant and occasionally the engine will shut off when warm.

Both myself and the mechanic have been checking it over. Coil packs and sparkplugs are confirmed working. I decided to test my injectors and they are also working, however, I also decided to test my wiring/voltage at the coil packs and injectors.

Everything checks out apart from the injector 3 wire that connects to the ECU which is currently measuring no voltage whereas the other 5 injector wires connected to the ECU are measuring about 12 volts. I believe this is where my problem is, I've done a continuity test on the injector 3 wire and the wire is allgood. Its not reading any voltage at the injector 3 ECU pin.

I'm really lost here and need some help trying to figure this one out, could it be a relay? could bad ECU ground affect this? is my ECU toast? a fuse? going to get the ECU tested soon but just thought someone might have some insight.

Thanks heaps for any help!




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