A leaking cold start valve wouldn't cause a lean condition, so it shouldn't misfire - if anything you'd run constantly rich.

TPS is probably not the culprit, because it wouldn't have any affect at idle - it would cause stumbling and such off-idle.

Could be the EHA, maybe not - have you tested the current to it?

The fact that it only happens on the first start-up of the day is very strange indeed.

When you say "...the engine idles glass smooth for the balance of the day, regardless of the number of restarts.", does this include re-starts where the engine has managed to get all the way back down to ambient?

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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.