Car won't start after change ignition wire

[iZDatsun]

I have a 77 280z 2+2, I changed the ignition wire and the car won't start. Please help. I'm new to the Z scene.

Thanks in advance.

[ctc]

Which wire did you replace? Can you be more discriptive. Why did you replace it? Do you have the factory service manual from this web site:

 

www.xenons30.com/

[Fuzzydicerule]

Did you change all of the wires or just one? If you changed all of them, did you make sure that you connected them in the right firing order?

[iZDatsun]

The wire was old and flimsy. I have the Taylor wire from MSA. Yes I have the service manual. I changed the spark plug wire on my 77 280z and now the car would not start.

I first put the wire on wrong and then fixed it based on the diagram on my haynes manual.

The battery somehow got drain. I jumped it with my g35, have power and the car would not start. It crank, but nothing. Once I unhook the jumper cable from it, the car later loses juice. This time when I try to start it, I hard this big thump sound from the engine. I think see something slowly leaking from the intake, end up to be gas. Did the intake backfire? I heard this the other day when the car was running perfectly. I live in Minneasota and it was about 10 degrees today. Did the fact that I first plug the wire in the wrong order has to do with the drain battery? I'm new at all of this so thanks for the advice so far.

[josh817]

If you were running Pertronix or an electric ignition module (little black box mounted on the side of the dizzy with two wires), and hooked the 12v to the module up wrong/backwards, you could have blown the unit and thus have no spark. No spark+fuel, no run, and you already said you have fuel.

 

Just go down the line of ignition by doing this:

-unhook all the spark plug wires, take one and move it close to a KNOWN ground (close as in only a small gap for a spark to jump across), have someone crank her over, do you see a spark? If not then continue further below

 

-unhook the center plug wire on the dizzy that goes to the coil, do the same thing as above and hold it close to a known ground, have someone crank her over. The coil should spark 6 times more frequently than the single spark plug wire you tested because the coil is firing for every cylinder, not just one. See a spark? If not then:

 

-make sure you are doing this on a good ground. How do you do this? Well two ways, you can get a test light, hook it to the + side of the battery and touch several points that you think may be a good ground. It should light up and stay lit if you find a good spot. Usually the alternator adjusting mount or something clean and solid like that will work fine. No test light? Maybe you have a meter, set it to read resistance and if it has a "beep" option that tests for continuity then select that too. Put one lead on the negative side of the battery, use the other lead to touch spots around the engine bay that you suspect may be a good ground. If you have a beep feature, it should beep when you find a good spot (telling you that there is continuity between the ground on the battery and the spot you found). If you don't have a beep feature, the resistance should measure pretty low if not close to 0.

 

-try the two tests above, with your newly found GOOD grounds, if you think you the place you were trying to get a spark at before was an insufficient ground.

 

-still no spark?

Pull out your test light or meter. The way the module works to my understanding is that there is a magnetic pickup sleeve in the dizzy. Every time this magnet rotates and pass by a certain point, the pick up sense it, then sends the signal down one wire, to the coil to say "spark now". By testing to see if you had spark at the plugs, we checked to see if perhaps your cap or rotor is bad. By checking the spark plug wire that connects the coil to the dizzy, we checked to see if you even have a signal from the dizzy or computer telling the coil to spark. At this point, if you don't have these things, we must answer the question as to why there is no signal telling the coil to spark, or why the coil isn't putting out spark.

 

There are three possibilities to this:

1. No signal to coil

2. There is a signal to the coil but no 12v at the coil to initiate the spark

3. There is a signal and there is 12v, the coil could be bad or blown from the wrong hook up, in other words "you need a new coil"

 

It's going to be difficult to test a signal to the coil when most of us only have a simple meter or test light, so we can't really test for that. We can however test for 12v at the coil. If you're running electronic ignition where two wires from the dizzy go to the coil, rather than an ECU, like Pertronix or the black box module, then we can likely assume that your 12v at the coil is making its way into the dizzy if hooked up properly.

 

Following this setup:

From DatsunZGarage - http://datsunzgarage.com/engine/

 

If you're not running this setup and your ignition is being controlled by the ECU then this is the last step I can really help with. The coil should have 12v to it, regardless of Pertronix, black box module, ECU controlled, whatever. After that, I don't know how to play with the ECU and test it or if it is likely to get messed up by hooking up ignition wires improperly.

 

Ok so testing the 12v at the coil... Take your test light or meter, place one end of the light/one lead of the meter and touch it to the + side of the coil. Touch the other end of the light/other lead of the meter to a KNOWN good ground, with the key in the "Run" position (with the key on basically), you should read 12v/the light should shine.

 

If you find 12v, we assume that you have 12v going down one wire towards the dizzy, and the module is putting out a spark signal to the coil/tach as the diagram shows. No 12v? Try jumping a wire with alligator clips, hell even duct taping some wire from the + side of your battery over to the + side of the coil, and see if it starts/run through the previous tests. If it does run then your problem was between your coil and ignition switch.

 

Now that you have 12v at the coil and presumably the module/dizzy, the only thing left to do if it still doesn't run is change the coil. We do this because of the three things listed above, we can only try two of the three unless you have equipment to test for signals like an oscilloscope and then... I suspect you wouldn't be in this predicament. By changing the coil to something you know will work or most likely did work so should work now (granted your current coil is probably fine but we don't take that for granted while trouble shooting), you eliminate that factor. 12v + good coil + ??? = spark, ??? = is there a signal from the module/Pertronix/ECU?

 

Other than that, that's all you really need for the Pertronix/black box module type ignition to work. 12v to the coil, two leads from the dizzy hooked up PROPERLY to the coil (switching these will blow the unit), spark from the coil wire, which then is distributed to the individual spark plug wires through the rotor-cap assembly on the dizzy.

 

As for an ECU.... Don't have a clue.

Edited February 13, 2012 by josh817

[iZDatsun]

Update. I got it guys. Thought I had to get new plugs or coil, it was the battery. Battery was so drained that it would not hold the charge.

Lol. Thanks for the help.