I have a '77 280z that won't run. I was out of town when my dad bought it, but he was able to drive it home fine. Now, it'll turn over, but it won't start. If I spray ether into the intake, it'll run for a minute. We're pretty sure it's something electrical that's wrong. We've replaced the EFI relay.

The fuel pump won't run, at least not how it's supposed to. If we hook power directly to it, it'll work fine, and we have fuel all the way up to the fuel rail at least. Plenty of pressure. Even if we have the fuel pump hooked up like this, it won't fire. The 2 wires which are supposed to hook up to the fuel pump have about 10.5 volts, and if we try to start the car, those wires jump to about 10.8 volts. However, if we connect the wires to the fuel pump, as they're supposed to be, for some reason it drops to about 2 volts. What sense does that make? Anyways, since either way we didn't have a full 12 volts, we thought that the positive wire might be shorting out somewhere. There's the black negative, and the positive is green with a blue stripe. We tried following it to wherever it goes, but couldn't find it...whoever previously had this car taped up all the wires with black electrical tape. I thought I followed where it was going, but every place that there were wires coming out of the big taped up one, I didn't see the green/blue. Where is this wire supposed to go to? And obviously any other thoughts on why this isn't running is appreciated.

Thanks in advance for any help...let me know if you need to know anything else.

Clay

 

Try disconnecting the small wire from the starter and turn the key to the start position and the pump should run. Reconnect that and with the key on push open the flap on the afm(intake hose removed) the pump should run. When you turn the key on you should hear the fuel pump relay click. Its under the dash on the ds just above the ecu.
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