what does car code P0125 mean?
It means that the engine never gets hot enough for the computer system to control the engine properly, causes could be, thermostat stuck wide open, error in ECT sensor or circuit, engine control module failure. A "live data" scanner would be the best piece of equipment to help track this down, with it you could see in actual time what the sensors are showing and the computers response to those readings are, and be able to go from there on what needs to be done.
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