It's the fact that the windings are immersed in fuel. Yes, they were stout, until ethanol started eating them. ...

Not to mention stock LT1 fuel injectors are JUNK. They were never designed to handle ethanol. Buh-bye!

Replace the ignition coil. Every LT1 I've had with a weak startup has had a failing ignition coil. In fact, you ought to consider replacing the coil and ICM just as maintenance. They both wear out.
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