Duffy's 1/71 Series 1 240z build

[duffymahoney]

Sounding good! 

[BoldUlysses]

Looks (and sounds) great!  That smushed breather hose coming off the cam cover doesn't fit with the cleanliness of the rest of the build though...  Maybe it's temporary?

[duffymahoney]

1 hour ago, BoldUlysses said:

Looks (and sounds) great!  That smushed breather hose coming off the cam cover doesn't fit with the cleanliness of the rest of the build though...  Maybe it's temporary?

I will have to fix that little pinch. I like the stock style hoses. Adds some style to the hoses. 

[conedodger]

Now drive it and let Haltech do some tuning! 

[duffymahoney]

Well I am a liar. My wiring was wrong. Iac wasn’t even working. But it lets by 20% air or so with 0 volts. So this is cold start with 20% air going by. On my haltech  You can set voltage at a percentage of 0-12v. So roughly set the lowest voltage it can go to 33%. Should work, but to be determined.  I need to run a new DPO wire

[duffymahoney]

I’m trying to track down a short in my 12v positive from my tach to my coil. I seem to have two black and white wires and a green a white in my coil bundle. Any ideas? The 2nd b/w and green/white doesn’t show up on any wiring diagrams. I have a 1/71 build.

[SteveJ]

Both black/white and the green white wires show up in wiring diagrams. See attached for the highlighted path.

One black/white goes from the ignition switch to the ballast resistor.

The green/white lands on the other side of the ballast resistor and goes to the tachometer.

The other black/white comes out of the tachometer and goes to the coil positive.

If you think you have a short in the circuit, unplug the 4 wire connector from the back of the tachometer and lift one of the wires off the ballast resistor. You have isolated the wires from one another and can measure resistance to ground at each.

 

 

 

Ignition Circuit.pdf

[duffymahoney]

Steve you rock! 
 

The coil positive has a full short in it. Haven’t found it yet. 

[SteveJ]

Now that you have isolated the wire, disconnect the connectors between the dash harness and engine harness that have a black/white wire and re-test.

If you have taken the dash out of the car during the build, I would wonder if maybe pinched a wire or the wire harness in the dash harness.

Also look for previous owner modifications like a relay for a thermostat-controlled fan.

[duffymahoney]

18 minutes ago, SteveJ said:

Both black/white and the green white wires show up in wiring diagrams. See attached for the highlighted path.

One black/white goes from the ignition switch to the ballast resistor.

The green/white lands on the other side of the ballast resistor and goes to the tachometer.

The other black/white comes out of the tachometer and goes to the coil positive.

If you think you have a short in the circuit, unplug the 4 wire connector from the back of the tachometer and lift one of the wires off the ballast resistor. You have isolated the wires from one another and can measure resistance to ground at each.

 

 

 

Ignition Circuit.pdf 1.85 MB · 3 downloads

Both the other green and white and other black and white are not shorted. 

[duffymahoney]

3 minutes ago, SteveJ said:

Now that you have isolated the wire, disconnect the connectors between the dash harness and engine harness that have a black/white wire and re-test.

If you have taken the dash out of the car during the build, I would wonder if maybe pinched a wire or the wire harness in the dash harness.

Also look for previous owner modifications like a relay for a thermostat-controlled fan.

I have never taken the dash out. 
 

I will have to try and find the engine wiring harnesses connector. 

[duffymahoney]

So the green and white should be a ground? Then the other black and white should be another keyed 12v? Do either share any wire? 
 

I honestly only need a single 12v for my ITB iac. That’s isn’t shorted. So I could abandon the shorted one.