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The v2 is over a year old with a very strange problem to me. Background: Life- 168 days+, 28km of filament, owned 1y2m. Upgrades- e3dv6 a year ago, trucks and arms within a month of them being released (both awesome upgrades). The dilemma is it started printing poorly (delamination between layers) within the last week. The meter thermocouple says it is 20-30 degrees below the value given by the rambo (Repetier). Completely soaked and cleaned hotend and reloaded Repetier to no avail.
Bad thermistor or bad board is the question? or best guess ... looking at replacing theristor first.

Sounds like a bad thermistor. At room temp what ohm reading is your thermistor at?

I've had a thermistor go bad on my printer before as well, reading higher than it actually was. Replaced the thermistor and it all worked properly again.

They're cheap, it's an easy fix, I'd say that it's worth trying.