MSD Troubleshooting - forumsey Feb 14, 2019If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.6AL-2 Programmable low voltage code, possible faulty boxMay 28, 2018Digital 6 Plus 6520 issuesJan 19, 2018See more results optispark ignition info | Grumpys Performance Garage garagepysperformance››C1-C6 CorvettesApr 11, 2018optispark ignition info. but if your seeing arcing down near the opti-crap its either a loose wire or an indication the opti-spark might need routine maintinance (like a cap, rotor)or a rebuild. If the optispark has been upgraded with an msd unit, there is a timing adjustment on the unit.