I have a spare opti with harness, icm, coil and just replaced the plugs. If the temperature is over 95 the car will die like the key was turned off. Its done this for 2+ months and will not do it unless its real hot out. I swapped the above parts to make sure they are not the problem. The fuel pressure does not drop at all and there are no codes. The first 2 times the car started up immediately and usually within 5-10 minutes after that. It was 107 today and did it twice and had to cut the trip short. I am positive it heat related but not sure what part or parts to check next. When I try to start it, the engine shakes but just turns over like if your out of gas. Any ideas?

 

Perhaps the ignition control module is overheating. Is it spaced away from the head?

 

The icm is brand new and has been moved away from the head. Someone at work suggested it might be vapor lock. I checked the gas cap and it had cracks around the rubber seal so i replaced it and we will see if that works.