1979 FJ40 no spark issues (I have read all the threads on this issue) What am I missing or failing to check (1 Viewer)

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I am guessing no spark at all? A quick swap back to the old cap and leads might be worth a test. When it died, was it instant or spluttering?
Also check the ballast resistor . You can short it out briefly to test for spark without damaging the coil.
 
I found this info. Does yours have a inline ballast?
78-80 coils work with an inline ballast resistor wire in the vehicle harness. It's possible to run the 78-80 igniter& coils on full 12V with no ill effects.

Edit, beat me to it, temporary full 12 v.. run a wire from battery + to coil + and crank it over.
[you can remove the 7v ballast wire from coil + when testing]
 
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Here is how to trouble shoot it:
1. Pull distributor center spark wire and place it 1/48 inch from block, Remove wires at + and - side of the coil. Run a wire from the battery + to the coil + and momentarily ground the coil - lug. If you get a spark then the coil is good.
2. Reconnect the original wire at the coil +, turn the ignition on and momentarily ground the - side of the coil. If you get a spark, then the key on ignition wire and ballast resistor are good. If not, they are bad.
3. If good, reconnect the original wires at the - side of the coil. Remove the distributor cap, turn the key on and manually ground the points. If you get a spark, then it should start. If no start, the igniter is bad.
 
Then after about 30 minutes it just died, no sputtering
Hopefully it's not the igniter. Have you got a spare?
Sometimes it's bad solder joints. If your feeling adventurous, resoldering cracked joints sometimes fixes things like this. I have revived a couple of igniters before. A mercedes and a yamaha , not a fj40 though.
 
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Hopefully it's not the igniter. Have you got a spare?
Yes but it was for another toyota. I hooked it up with the same results. The wiring diagrams have me confused as they call for a Black and White wire coming from the starter to the coil positive post but I don't have one. The starter Black wire with the white strip is present at the starter but there is no Blk and White wire at the coil/ignitor
 
I will shortly. The new Denso coil that I got from the local Toyota dealer Ohm'd out to the same specs as the original Toyota Denso that I removed. What's the chance of getting a new bad coil?
1.6 on the primary between the two posts and 13 ohms on the secondary from the + post to the center cap out to the distributor cap center
 
Hope this helps a little.

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It is hard to measure the difference between 0.5 ohm and 1 ohm with a cheap meter. You need a meter that has been standardized by a means that is traceable to the national institute of standards and technology (NIST).
 
@pinhead
Here is how to trouble shoot it:
1. Pull distributor center spark wire and place it 1/48 inch from block, Remove wires at + and - side of the coil. Run a wire from the battery + to the coil + and momentarily ground the coil - lug. If you get a spark then the coil is good.
2. Reconnect the original wire at the coil +, turn the ignition on and momentarily ground the - side of the coil. If you get a spark, then the key on ignition wire and ballast resistor are good. If not, they are bad.
3. If good, reconnect the original wires at the - side of the coil. Remove the distributor cap, turn the key on and manually ground the points. If you get a spark, then it should start. If no start, the igniter is bad.
Steps 1 & 2 checked out and I got a tiny spark with each.
As for Step 3. Grounding the points. I don't have points. I have a signal generator. Can you please elaborate?
 
It is hard to measure the difference between 0.5 ohm and 1 ohm with a cheap meter. You need a meter that has been standardized by a means that is traceable to the national institute of standards and technology (NIST).
I think Pinhead means a Fluke meter.
Ah. I have an iEquus Innova 3320 and MW 7137. Definetly not the best meters.

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@pinhead

Steps 1 & 2 checked out and I got a tiny spark with each.
As for Step 3. Grounding the points. I don't have points. I have a signal generator. Can you please elaborate?
@pinhead
Would grounding out the white wire ground from the distributor signal generator accomplish this?
 
What's the chance of getting a new bad coil?
Very unlikely. I have a theory how this could have happened.
Inline ballast was on it's last legs. The new coil drew a bit more current than the old one and finished the ballast off [explains the running for 30 mins then death], even though it gives 7v, it could be breaking down under load.
If this is the case , find the ballast and replace it or short it out.
With the 12v coil test you may have to leave the ballast 7v wire connected in case the igniter gets it's power from the ballast. [full 12v won't hurt the igniter]

Or none of the above lol.

The diagram from fjcman shows the igniter has full 12v , the ballast is only for the coil, so removing the 7v wire won't make any difference with the 12v coil test
 
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Oops. I forgot you have a ‘79. You have replaced the igniter and it doesn’t run, so that points to the pick up inside the distributor as being bad. Try replacing it.
 
No sorry, that diagram is out of a chassis & body fsm. I think the testing you posted trying to help Wadesters ( 1979 fj40 no spark issues) post #31 applies to 79 ignition also.
 

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