I have a 1994 NA 2+2 that has a Check engine code 51 Fuel injection. I used conzult software to try and reset the error. it comes right back. The software allows me to shut down each cylinder 1 at a time, and cylinder 1 does not change the way the car idiles. I then used a Stethoscope to listen to cylinder 1 and I do not have the same "tick" that the other cylinders have. just looking to make sure that I have not missed anything, i thought i read that the Fuelinjector has a resitance value i could measure , but i'm not sure what it is. Please let me know if it sounds like I missed something.

thanx

Rob

From the TwinTurbo.net web site.
We now know which injector(s) are suspect. To scientifically prove the status of the injector it must be measured. An Ohm meter will be required to measure the resistance of the coil of the injector. With the engine off, the connector to the suspect injector(s) will need to be disconnected to gain access to the injectors terminals. A little trick to doing this (because removing the connector is by far the hardest part of the diagnosis). Grasp the connector by the plastic plug and carefully pull on it. There is a retaining clip that keeps them on (very good) but with enough "carefull force" the plug just pops off without the whole hassle of removing the clip. Overall be gentle with the wiring harness, they can become brittle and are expensive to replace. When access to the injectors terminals is had, measure the resistance (Ohms (Omega Symbol)) of the injector. If the meter is not auto-ranging, put it in the 10-20 Ohm range. The factory specification for a properly operating injector coil is between 10-14 Ohms. For instance: if the injector is 27 Ohms or 8500 Ohms or Infinity Ohms then it is defective and must be replaced.

Thank you , I will give that a try ....

Rob

If injector is in spec, try cleaning the connector and injector terminals as they are most likely corroded badly. This is very common.

Injector failure is very common now due corrosion inside the injector itself occurring because of age. There is only one fix, to replace them.
I do more injector replacments then any other service on the 300zx.

Pulled the plug , the injector had 868 ohms ... all others were 11ohms ... so I need to look arround for a new one... Thanx Rob

I believe I have them, $35 ea. if you like.

contact me direct at rich@rdz300.com and I will check to make sure they were not sold.

Just another bit of info. Because the one injector went, then the others will follow. Tis the nature of the design on our cars. That corrosion and age thing again.

Rich

I learned about that at our last monthly meeting!
It was a really informative lesson about the Z31 and 32 cars. Never appreciated how truly great they really are, and I learned what to watch out for on them. The guy who invents a way to keep the injectors "age-proof" will retire young!
Frank