First, I'm not a mechanic at all, only speaking from personal experiences. Ive just had a similar problem. My car was thrown into limp mode with the wrench signal simply because I was running on fumes to the gas station. Wrench light went off and ran normal after 1/2 tank fill up. Most autopart stores check engine
lights for free if don't have a code reader. A visual inspection of the motor including all hoses, wires, and sensors can go a long way.