Plugs Losing Spark After Engine is Warmed up.... WHY ?

[Yinzer]

 The engine in my 86 720 starts and runs fine after Cold starts. However, once it's warmed up and shutoff it will NOT restart. It will only restart after sitting several hours and cooling off.

 

 I've traced it to the Ignition. The plugs are not getting spark after the engine gets hot. It WILL stall out and leave me stranded. It only restarts after sitting for several hours.

 

 The cap/rotor/plugs are new. Timing dead on.

 

 Is the Ignition Control Module bad perhaps ? How does one check it ?

[datzenmike]

Do you have the Z24i engine? with EFI???? Has two wing nuts holding the air filter on. May say Electro-Injection on it.

 

 

[Yinzer]

4 hours ago, datzenmike said:

Do you have the Z24i engine? with EFI???? Has two wing nuts holding the air filter on. May say Electro-Injection on it.

 

 

 No. It's the Carb'd version.

[datzenmike]

GOOD!!!!

 

Intake and exhaust side plugs are both not firing?

 

Sounds like a thermal intermittence problem. 

 

Get a cheap test lamp and see if there is 12v on the positive terminals of the coils with the ignition ON the next time it fails. 

 

If power is there, get a aerosol can of Super Cold from Amazon. It's not cheap $20 Canadian so probably $15 US? Take the distributor cap off and spray below the rotor where the ignition module is located. If this cooling effect gets it going then the module has the problem.