help! my car wont start , no power in the spark

[radZ77]

hi , i have a 1978 280z i drove it fathers day and then parked it out side , ever since then now my car wont start...

thing i have checked

all harness looks good , no spark in the wires

then no spark in the coil

replaced the coil but nothing

no power getting to the coil

(my starter is with switch to the battery)

checked the ignition switch . i replaced it but nothing

normally my stock voltage gauge would show power when trying to start the car but this time it just reads 0 all the time

my rmps dont jump when trying to start the car ... i know they used to plus that would of meant i had power but since i dont i have no idea

i checked my fusable links and replaced them but nothing again

i discounted the ecu just to reboot it but nothing .....

what im i missing or doing wrong . the please help me . i need the car running

POINT IS THAT I AM NOT GETTING POWER TO THE SPARK SO CAR WONT FIRE!

[grantf]

Try testing\examining the transistor ignition unit. It's a shot in the dark, but when I had the same problem that's were I found a loose ground. I am not saying that this is you're problem just another possible place to look.

Good luck. GF

(oh and my car is a 78)

Edited November 15, 2010 by grantf

[Zed Head]

"starter is with switch to the battery" Do you mean that you can power the starter separately from the ignition switch?

Sounds like you should make sure you have power to the ignition switch.

Make sure that you have power to the fusible links also. On my 76, three of the four fusible links have 12.7 volts all the time, key off. Only the headlight link does not. If no power is running through the fusible links then you can trace the lines in to them to find out why not.

The old Z ECUs don't reboot. They're not like the modern ones, they just take signals from the engine and sensors and then send signals out to the injectors.

[radZ77]

yea my starter is seperated from my ignition switch ...

but i also tried another ignition switch i had and nothing ...

shouldnt the voltage gauge show power tho at all times on and off...

so trace the power on the fusablelinks, will do tomorrow with a volt meter

[SteveJ]

Look at this thread to find a color version of the 78 wiring diagram. It could prove helpful to you.

[Zed Head]

yea my starter is seperated from my ignition switch ...

but i also tried another ignition switch i had and nothing ...

shouldnt the voltage gauge show power tho at all times on and off...

so trace the power on the fusablelinks, will do tomorrow with a volt meter

It sounds like the wire to the starter lug, where the positive cable from the battery is also located, may not have a good connection. It's the wire that goes up to your alternator, but along the way all of the power to the car is spliced off it up through the fusible links. Take a close look at the main lug on the starter. You should have the big cable from the battery and one more heavy gauge wire that disappears in to the wiring harness. That would explain the "zero" voltage reading.

SteveJ is right, that wiring diagram will help you out. I think that you'll have to unzip it though.

[FastWoman]

There's a whole gaggle of relays inside that big, black housing the fusible links are mounted to. You should hear a big "click" from there when you turn the ignition key. If you don't, then the system indeed doesn't have power. Fusible link assemblies are a common culprit, although you say you've addressed that issue.

You might have a corroded assessory wire coming off the positive cable to your battery. Look for a crunchy bulge beneath the insulation, right by the cable connector.

[radZ77]

thanks im going to try all the advice you guys have gaven me . i will repost once i finish checking all that...