92LT1 dies at 140f water temp

[VetteLuv]

Vette starts & runs great until it warms up to about 140f then it "stumbles" or dies completely. This happens when driving or at idle in the driveway.
An electric failure is indicated as all gauges "die" with the engine. When motor dies completely it will restart immediately with a turn of the key and will run & drive without any problem whatsoever. The "Service Engine Soon" warning light is set and stays lit until car is off for several hours.
Reading the error code indicates a malfunction of the Optispark: signal drop-out. Optispark was replaced just before going into storage for winter of 2014-15 and Vette ran OK for that very short time. Last summer started OK but started having the problem in September after only about 1,000 miles on the new Optispark (Limited driving due to health problems). After another winter of storage the problem continues (as does out winter weather). Before taking the car to a plug&play repairman who will probably want to replace the Optispark, and the almost new water pump, does any C-4 wizards have any suggestions and/or solutions.
Thanks,
Bruce

 

[DonB]

I have NO hands-on experience with the Optispark, but I've studied it. I have the '90 L98 with a distributor(and frankly after studying the Optispark, I'm glad I do.) NO Offense! BUT, before replacing that expensive system and all the grief involved, I think a check of the temp sensor and especially its wiring to the ECM wouldn't hurt. Especially the often overlooked GROUNDS!
Also, 140* isn't very warm at all and I'm sure if it was a thermal condition in the pick-up coil(as in regular distributor set-ups) it doesn't cause a problem till it gets nearer to operating temps, but 140* is near where the temp. sensor's values start to signal changes to the ECU. A resistance check may shake out some gremlins. I'd also check the unit for moisture since due to it's location it is very susceptible to condensation and since you just brought it out of storage........ Open it up and dry it out. Clear the codes and try it again.
Also,..Sometimes the trouble codes are general and vague. The computer just knows there is a problem in the Optispark, NOT necessarily what exactly it is that is causing it.
Good Luck.