Q: Can a loose map sensor make your car sluggish and no power

As long the MAP sensor is sealing vacuum on the intake manifold. If it is not, then it may be causing low power. You may have an incorrect part if it does not fit like the old one. Take in the old one and new one to the parts store and verify the part is correct. Also have another scan for codes and see if the codes are clear after the new MAP was put on. You may have another issue that needs to be diagnosed. A manifold leaking vacuum can also give a bad MAP sensor reading. If you don’t want to bring it back to that shop, a certified technician from YourMechanic can come to your car’s location to inspect the car’s loss of power and let you know what steps to proceed with next.