No Spark issue. Negative voltage on ignition switch.

[280zdude]

So basically I put starter fluid down the intake and i got huge back fire out of the intake! 
 
so I tried it another way and took the spark plugs out and shot some in there.. but the car did not run for a little while it.. kind of turned over quicker? 
 

Never used starter fluid But I didn’t spray too much. Couple squirts 

 

just wanting to say- someone definitely played with the fuel system it was disconnected and plugged.. 

 

Merry Christmas!

Edited December 25, 2020 by 280zdude

[280zdude]

 

On 12/23/2020 at 5:26 PM, Zed Head said:

The injectors and fuel rail might be fine or they might be rusty.  It's hard to say.  Disconnect a few lines and look inside.  Fuel filter and cold start valve are easy to get to.

The Body Electrical chapter shows where all of the relays are and has a drawing of the fuse box.  Also has many small wiring diagrams that are very detailed.  Spend some time there, and in Engine Electrical and in Engine Fuel.

The 1977 manual isn’t in the manual was sent me early 

[SteveJ]

9 hours ago, 280zdude said:

So basically I put starter fluid down the intake and i got huge back fire out of the intake! 
 
so I tried it another way and took the spark plugs out and shot some in there.. but the car did not run for a little while it.. kind of turned over quicker? 
 

Never used starter fluid But I didn’t spray too much. Couple squirts 

 

just wanting to say- someone definitely played with the fuel system it was disconnected and plugged.. 

 

Merry Christmas!

That is likely a timing issue or the intake valves aren't closing tightly enough. It's difficult to guess without examining the engine. However, I suggest you get your fuel system working right.

In the meantime other things to consider is adjusting the valves. Adjusting them cold is not the preferred way, but it will work.

[wal280z]

On 12/23/2020 at 4:23 PM, 280zdude said:

http://www.atlanticz.ca/zclub/techtips/wiringdiagrams/F77ZCAR-WIRING1.pdf

 

This is the wiring diagram I have been using for 1977 280z

Many errors have been found in that version and fixed with later revisions, It is now Revision 'N'

The diagram in the download section is the diagram that you need.

[Zed Head]

Thanks, I finally figured out why the version I had has an F in front of the file name.  Updated mine to this new version.

[280zdude]

Update on the fuel electrical.. I’m getting .03- .05v to the pump wires. I’m guess it may be a bad ground or relay? 

 

[280zdude]

2 minutes ago, 280zdude said:

Update on the fuel electrical.. I’m getting .03- .05v to the pump wires. I’m guess it may be a bad ground or relay? 

 

[SteveJ]

Describe the testing conditions:

Key position?

AFM flap?

If the key is on ON with the flap closed, the relay is not going to complete the circuit to supply power to the fuel pump.

[280zdude]

The fuel pump relay does click when you put the car in the on position. How do I check if the voltage coming out of the relay is around 12 volts? Can I tried to unplug the connection between the relay and the green and blue wire in the car but it seems to turn the relay off. 

[SteveJ]

You will need a probe that can reach inside the connector at the fuel pump relay. That will also mean you will need someone to move the flap in the AFM while you are measuring voltage. You will not see voltage for the fuel pump relay unless the key is in START or unless the key is in ON with the AFM flap open.

[280zdude]

45 minutes ago, SteveJ said:

Describe the testing conditions:

Key position?

AFM flap?

If the key is on ON with the flap closed, the relay is not going to complete the circuit to supply power to the fuel pump.

Key is on the on position afm untouched. I will try that. But when the car is on and fuel pump doesn’t make any sound. 

 

I will also do the probe suggestion! And let you guys know what I find out 

[Zed Head]