New to LS1Tech, I own a 95 Z28, Problem: drove the car from the house to work, (20 miles) car would not start during lunch. Checked for spark at spark plug no spark. Checked for spark at coil no spark. Conclusion bad coil, ICM or Opti. I purchased a MSD Opti still will not start, Changed the coil still no spark, changed the ICM the car starts. (Trial and error) Two months Later while driving car shuts off but turns back on, latter that day leave to go to store come back out car will not start waited 10-15 min car started up. Looked for codes but no codes found. Two days later while car is idling in parking lot car shuts off, waited 10-15 min no start, tried to start it through out the rest of day no start. Towed car to my brothers house 105 miles away checked for spark on wires and coil had spark but was really weak or no spark at all. Changed the relay from the MSD Digital 6 to the Coil car started up, But still having the same problem car still shuts off and it still takes 15-20 min. before it will start, ended up it was not relay from the digital 6 box. now its reading codes 16-Low resolution pulse 41- No ignition control circuit, 42-ignition control circuit, check the wiring and connectors between the ignition module, replace Control module or ECM/PCM if needed and 51- PROM/EEPROM error, Called and talked with MSD we both concluded that it was the opti,(had a small amount of oil that was effecting the optical eye) called and talked with Summit Racing, Opti was still under warranty Summit sent me a new MSD Opti. Replace Opti made my trip from Colorado to KY. Car died on me again (Opti) code 16 and 36. Still under warranty Summit is sending me a new MSD Opti. Through all of this I still love my LT1, just helps me to understand my car better. Oh just have to thank the Guys at Summit Abe in Customer service and Mike in the Tech department for all their understanding and help. Question what could be making me go through Optis like this?

 

I'm no pro but to have that many msd opti failures that fast would be pretty high odds. check opti harness, and main harness for the proper voltage.

 

Unless they've improved their product, MSD optisparks have been known to have issues. A lot of people seem to get decent results by putting some locktite on the rotor screws. An OEM opti would probably be better, and cheaper.

 

Have you taken your MSD Opti's apart, and checked them out before sending them back? This might give you a better understanding of what's going on. I know with my '94, the drive pin was a little too long, and the rotor in my opti actually came into contact with the cap, and it basically destroyed itself in under 20 miles.

I went back to an OEM opti, and no issues since... (knock on wood!!!)

 

The MSD opti was a large mistake, stock is more reliable.

ICMs need a thermal transfer paste applied or they will overheat, did you do that? Your problem could possibly be an overheating ICM they will act up hot then work once they cool, there are other failure modes but this is one of them.

The MSD boxes are a complete waste on a stock car or even most NA cars. Plus they didn't get the nickname Might Suddenly Die for no reason.

You will find your car to be more reliable and just as powerful if you run a stock ignition.

Right now I run stock ignition, if anything the car got slightly faster on track when I disconnected the ignition box I have underhood.

This is NOT a 70s or 80s car where ignition upgrades are tried and true. Here ignition "upgrades" usually just lighten your wallet and cause issues.

 

96capricemgr.
I agree about the MSD Opti a big waste of my time and money, but for now summit is replacing it for free. If it goes out again then I’ll ask summit to replace it with the stock OEM Opti.
On the “ICMs need a thermal transfer paste applied or they will overheat” yes I did, a little pack comes with every ICM + I bought an additional 2 packs.
Dadic: 78: yes, I have taken the opti apart on the first one I found that some oil had soaked through and had saturated the optical eye that was the failure on the first Opti; I am currently changing out the PCV valve, and was wondering if oil could have seeped down one of the vacuum lines into the Opti? Can Anyone answer that one? On the seconded one, I didn’t find anything visually wrong so I can only assume that the codes (16 and 36) are right and that it is the Optical eye.
BTC: Talked to Summit and of course they are telling me that this Opti is the best out on the market. Did the locktite on the rotor screws.
Pro94lt: what is proper voltage, on the opti harness, and main harness.

thanks again for all your help-Jake

 

I don't know what else to tell you, bro... All I can say is that I've had the same issues two times (both with MSD Opti's) and finally just got an OEM, and haven't had any issues since. Maybe after your next one blows, give the sales rep at Summit a good explination, and see if you can upgrade to a stocker.