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77 280z no spark


ISPKI

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Hey guys. Trouble shooting my 77 280z, trying to get it on the road... Heres the deal: The car is somewhat stock. The main mods I have done are: 280zx dizzy with E12-80 IM. Fuses upgraded to new fuses and fuse blocks. I drove this car into my garage to work on the body and oil leaks, helicoil the valve cover bolt holes, oil pan and front timing cover gaskets etc. I now have it all back together (minus body work that still needs to be done) but it will not start. Fuel pump is functioning according the gauge in the rail, but I cannot generate a spark. Checked all my engine grounds and they are all new and clean.

 

Looking at page 32 in the bible, I have tested for spark at the plugs and got nothing, checked spark at coil and get nothing. I attached a wire to the coil "-" post and attempted to manually trigger the coil with the high tension wire sitting next to one of the suspension tower bolts and grounding the wire out on one of the bolts next to it. The jumper wire sparks but the coil wire does nothing.

 

I am also having a hard time finding the "ignition lead wire" in the diagram on page 32 of the bible.

 

Tested Pin 1 for bat voltage with key in "on" position. Result: 12.6v. Anyone have any suggestions for the next step?

 

Just tested for Bat voltage on coil "-" and "+" posts with key in the "on" position. Both posts have 12.6v when key is on.

Edited by ISPKI
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Do you mean the high tension wire? I have pulled it multiple times and reinstalled it. It feels as though it locks in tight. To generate a spark off the high tension wire, does it have to be touching a ground or just near a ground?

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I tested the Ignition coil. Primary resistance measured 1.3, factory service manual calls for 0.45-0.55. Secondary Resistance measured 11.15, service manual calls for 8.5-12.7.

 

Primary is reading high, not sure why that would cause it to not spark at all though.

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Do you mean the high tension wire? I have pulled it multiple times and reinstalled it. It feels as though it locks in tight. To generate a spark off the high tension wire, does it have to be touching a ground or just near a ground?

It has to be about a spark plug gap's distance away from a ground point.  It can be closer or farther but if you go with that distance you'll be able to see it and also know that it's not too far.  If it's touching the ground point,of course, you won't see anything.

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Well I started testing ground points and found that the strut tower bolts have no continuity to the engine, which seems odd since the manifold ground is right next to them. I positioned the #1 spark plug to one of the bolts next to the hood latch and cranked the engine over and it sparked! But only a couple of times before I heard a crackling sound and the engine stopped cranking. I checked my fuses and could not find a burned one, but it now only cranks once and then stops...

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  • 2 weeks later...

I started troubleshooting according to the 1979 280zx book, since I have a 280zx dizzy. I measured resistance on the two connectors from the pickup coil to the IC unit, book says that it should read 400ohms, I get no reading. Will be pulling the pickup coil next.

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So I tested the pickup and it seems to be OK, measured 385ohms for resistance. I am at a total loss now, the coil is getting power when it should, the dizzy seems to pass it's tests, everything seems fine, but it wont spark. I decided to hookup a jumper cable to the coil after removing all the wires from it. I positioned the end of the high tension wire over one of the bolt heads on the intake manifold, then connected the jumper cable to the battery and started tapping the negative post, and nothing comes out of the high tension cable. I am wondering if the high tension cable is damaged internally somehow.

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