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I have an '87 N/A MKIII, it starts right up when it's cold and runs beautifully but after warming up and being shut off it wont start up again until it has cooled down. I did a little test and figured out that its not getting spark from the coil until it cools back down. Ive replaced the spark plugs, wires, cap and rotor as well as the coil itself but it still gets no spark after it has warmed up and been shut off. If anyone has any idea what this could be please let me know and thanks for reading! 馃槂
 

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When I had my 7M I had the same problem and never solved it. Somebody told me it could be "heat soak". Car would start up fine in the morning, and as I drove it throughout the day it would be harder to start.
 

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The 7M-GE is a pretty simple engine and the only thing that can cause a no-spark condition outside of what you've already replaced would be the distributor itself and the ECU. It's possible that after heating up the old dizzy is somehow failing to send a cam sensor signal on a hot start, which would cause a no-spark condition as you describe. I'd try a different distributor if you can dig one up, and if possible, duplicate the hot no-start condition and see if it's sending a cam sensor signal to the ECU.

If the distributor and cam sensor signal are good, I'd pop open the ECU cover and see if you've got leaking capacitors. Old ECU's with leaky caps do weird shit, but I think the distributor issue is more likely.

A tertiary thing to check out would be the coolant temp sensor signal to the ECU, which can cause issues with hot-starting, but that wouldn't kill spark - it would just fail to add enough fuel for a hot start so it'd take excessive cranking, and it'd sputter and choke a bit before it ran normally.
 
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