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Posted a picture of the roadster with the hood on. Note there are no louvers. I think that setting at the light caused heat build up under the hood which affected the fuel or Optispark. Fan was not on the whole time.
As a side note I pinched off the vacuum line going to the fuel pressure regulator and the pressure jumped from 37 to 42 lbs. This is a new regulator but as luck would have it I have a second new regulator which I will switch out soon.
can you rig the gage up so you can see it while driving and see if you can get engine to stall or stumble. low or high fuel pressure will not throw a code.
The LT1 is designed to run 205-220 degs If your engine bay was at 220 degs I doubt even the best fan and radiator could get your engine down to 180 degs. Also note an engine will reach it highest tempters about 10-20 minutes after you shut it off. If heat was being held in the engine bay you would see the temps shoot up after the engine was shut off. This is a test GM calls a hot soak. It is to verify the key off fan system is working. Last time I had to do one (not on a LT1) GM 220 running was normal and up to 240 after shut down was considered a pass. You could get a digital cooking thermometry just run a cable under the hood as you drive. They are cheap and accurate.
As for you fuel system and ignition. If everything is working properly then no, engine temps should not effect them much at all. I have seen many motors lock up because the motor overheated and drivers never knew there was a problem. A common occurrence is a large hose will pop off and the car will lose all of its coolant in a matter of seconds. The coolant sensor need coolant to trigger them and if there is no coolant they will show a very cool engine. Very quickly the oil will over heat. The complaint I would see is " I was driving and the engine lost power, then it shut off" The was the pistons growing so big the engine did not have the power to push the piston through the cylinder any more.
Just the other day I was driving my GTO on a Highway with construction and no where to pull off. My battery light came on. I thought the Alternator went out. It was the belt tensioner, it froze and stopped the belt. About a minute later glance down at the gages and saw the temp gage pegged. Engine was running fine. I shut it down and coasted to a pull off area. I got luckily that the engine was loose with a 130K miles on it and synthetic oil. Once a sorted out the belt/tensioner it is fine. Pegged is what 300 degs? Engine bay was so hot the fiberglass hood would not latch.
I did say if everything is working right. Vapor lock in an EFI is not really a thing due to the higher fuel pressure but you should still avoid fuel lines too close to exhaust and any electrical winding or wire/connection that is already failing and building up resistance can be made worse by heat. It might be a good idea to ohm out your coil and injectors and verify their cold resistance. Replace anything that at max or over resistance spec. Your original 94 engine would have a vented Opti-spark. They are very subject to moisture, even a very small coolant leak or moisture spray can cause issues. Newer Opti-sparks are sealed. The early opti-sparks sparks have other design flaws. Also the wiring cable that runs to the Opti is a known failure point. I am not big on throwing parts at a car but if that harness is original I would just replace it.
Thanks for the input Gorn. The wiring harness is all new as is the fuel lines (nylon). My problem was heat related but what did it effect to cause the misfire. Because the fuel is in constant motion I doubt it was vapor issues. That kind of narrows it down to ignition. Three items is the ignition system come to mind. First is the Optispark which is new, coil which is also new and the ignition control module (ICM). The coil and ICM are bolted to the head with a heat sink. that would kind of indicate there may be problems if those units get to hot. Maybe space them off the head would help.
At any rate I know I have to get rid of heat when not moving. The solid hood sides just helps to contain the heat of the exhaust headers so I'm in the process of putting louvers in the hood sides.
there should be some electrical grease between the coil and heat sink. I think the 94 has two temp sensors, one for gage and one for ecm/pcm. are you using a 94 ecm/pcm or aftermarket?
