Nissan Repair: fuel injector, nissan 240sx, volt ohm meter

Question
Hi Von
Can you tell me what is the proper voltage across the fuel injector terminal at engine running?Its a nissan 240sx car.
Thanks

Answer
What you want to check for is the ohm resistance on the injector to see if it works and you can do this without power on the system.  Simply unplug the injector and check the resistance with a volt ohm meter.  Go across the two pins and look for 12 ohms as a baseline.  What I do is check all the injectors and replace any that are really low or high from what the rest of them check.  Yes, it is the cheap way out and most people will want to replace them all as a set.  But, being cheap I like wrecking yards and I can get a set for what one new one cost at the store.  Then I ohm check them and get a close match on the set I install.  If you were wanting to back probe your harness to see if the injector is getting a signal all you would need is a test light to see it strobe when the injector is fired.  It is the injector most of the time that goes bad.