ZDriver.com - Help 300zx 3.0 na fuel pump problem?

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Help 300zx 3.0 na fuel pump problem?

I just bought an 85 300zx na. Doesn’t run. Guy said he thought it was fuel pump and I agreed. So I took the fuel tank out and the fuel pump out of that and it was fine put power directly into it and it turned on. Then I thought maybe it was just a relay. Switched out the relay with others that were good and it didn’t change anything either. The fuel pump still won’t turn on with the turn of the key. Does anyone know what my next step from here should be? I have the dash apart and I can see all the wires under the drivers side. Is there any way to tell where my problem is?

Start at the relay.

Check to make sure that everything from relay to pump is working correctly. In other words start by checking to see if the relay gets power (test with meter but you will also hear the audible click) when the ignition is turned ona and looses power when ignition is turned off. If the relay is working off the ignition then you problem is between relay and fuel pump. Use your twelve volt power source to test the relay and verify that putting power to the relay operates the fuel pump. If all is well between relay and pump just not getting power to relay when the ignition is turned on then start tracing from relay back to ignition. If you need a wire diagram I have one for a 88 and have a service manual for a 86 so between the 2 I could probably shoot you some pictures of the wiring diagrams and fuel pump diagrams. Also make sure to check all grounding to make sure it isnt just a loose ground or one getting a bad connection due to corrosion. Good luck!