My current tune runs perfectly, is nice and responsive… nice everywhere but after the engine warms up if you shift it into neutral it repeatedly revs quickly to about 900-1000rpm, just like someone was quickly tapping the gas pedal, maybe a little faster then once per second. After doing that about a dozen times it starts to settle down, sometimes going away, sometimes just getting not as bad.

If I put it in gear it stops (idles right around it’s set point), if I give it a little throttle it stops, it doesn’t do it when it’s cold at all, but if you shut off and restart when it's warm it will start up doing it… (L98, 42pph injectors, 165…)

I’m fairly certain that it has something to do with the tune/chip since I would expect that if it was a mechanical problem it wouldn’t settle down some on it’s own and it would persist when you put it in gear.

Any ideas what it could be or where to start looking?