Crackersauce

Welcome everybody, thanks for reading! Just got my first Vette in August! A 1994 base model with 108k. Did a tune up: O2 sensors, spark plugs, wires, coil, ICM, opti, water pump, fresh fluids, cleaned the throttle body, all fresh fluids and new filters, and replaced 2 rusted out core plugs with new brass plugs. Car runs perfect, it's everything I dreamed it would be after 31 years wanting one! Just one little issue....

I keep getting the ol' H42 Ignition Control Circuit Shorted code, but it's intermittent. I start the car, the SES light comes on, idle a little over 1k rpm. Give a little press on the gas pedal, engine revs down to about 600 rpm idle. Put her in drive, head on down the road, SES light goes away. The shop manual says that the code is supposed to shut down the injectors and disable the car completely, but that's not happening with my car. I've scanned and cleared the code several times, but every drive, the light stays on for about 1-2 minutes then goes away.

I have a new stock OE ICM and coil (both made by BWD, no MSD parts or anything like that) However, my optispark is a cheapie from O'Reilly Auto Parts: Richporter Technologies distributor part number GM22-price $212.99. I was trying to save some cash, which I did, but I'm suspecting now that if I return it and go with a solid more expensive AC Delco opti, my idle issue and H42 issue would go bye-bye. So what do you all think? Thanks!

rinosaur

Check all the wires from ICM and Opti and the ground from the ICM. Sometimes they get corroded, touch hot metal, or get really dirty. Also did you put thermal paste in between the ICM and the heat sink?

0ChandlerMotorsports

I just read a success thread with cleaning the connector on the optispark. Also another person had a short inside the coil.