1968 Ford Mustang — intercooler before adding more boost?

I wouldn't throw parts yet. Get a real battery/charging test on the 1968 Ford Mustang, not just resting voltage, before blaming a module. That's the branch I'd chase this week. Stop there until you know. Worth doing even if the car feels fine right now. That's my plan before I call anyone.

Intermittent stuff lies if you only catch it once. Move a coil or plug on the 1968 Ford Mustang if it's cylinder-specific and see whether the code follows. That's the branch I'd chase this week. On “intercooler before adding more boost,” that was the fork that mattered for me. Stop there until you know. If your situation is the opposite, ignore me. Heat soak after errands is the other window.

If it were in my driveway, swap the cheap/easy piece first on the 1968 Ford Mustang and see if the fault moves. That's the branch I'd chase this week. Verbal 'we'll take care of it' is not a plan. I'd rather be boring and correct. Happens in gear, not in park, for what that's worth.

This is usually cheaper to test than to guess. Write temp, speed, and in-gear vs coast when the 1968 Ford Mustang does it — then decide on parts. Save the big job until that test fails. Verbal 'we'll take care of it' is not a plan. That's coming from doing this as an owner, not a shop. No warning lights, which is why I'm documenting it.

Checked the easy stuff on the 1968 Ford Mustang and found one clue worth chasing before I book a shop. If it repeats twice more I'll book time.

OP update: scanned the 1968 Ford Mustang again and still only have the one pending code, no new lights. Trying not to diagnose from the couch.

If it were in my driveway, move a coil or plug on the 1968 Ford Mustang if it's cylinder-specific and see whether the code follows. Don't erase codes until someone who can help has seen them. Run the total, not the monthly, before you commit. I'd rather be boring and correct. This is me being the wet blanket on purpose.