Definitely going to be a resistor and not an actual 'chip'.
Going by the bad feedbacks, probably just a resistor that goes inline with the air or coolant temp sensor. Common cheap 'HP Gain' gimmick, along the lines of fuel magnetizers and splitfire plugs. Doesn't alter the fuel map at all, just tricks the engine into misreading the sensors.
I wouldn't risk it, much better methods of gaining power out there with much safer results. Heck, you'll probably get the same results from checking tire pressure and doing a good tune-up.
Now I remember what this reminds me of. Those 'emissions code readers', which were usually nothing but a jumper wire in a plastic box and cost $30. All they did was put a jumper between the contacts in the diagnostic connector causing the check engine light to blink. All the software was already built into the ECU in the car.
gimmick, gimmick, gimmick.... pure and simple
My oil line fix
My 100k stopped odometer fix
Brace for impact, I'm in a "modifying mood". Massive thread count inbound.