Prius Hybrid WAS consistently getting over 42 mpg but after serpentine belt was replaced my Meineke, it now gets only 30 mpg. What could they have done wrong?
They may have knocked a connection loose while replacing the belt. Are there any lights on / check engine light?
Yeah, check for something disconnected or not properly seated near the belt. Time to get the DTC codes read to help determine the underlying problem(s) with your car.
If the check engine light has always been on than there would be no way of knowing if anything had changed due to the service, other than your mpg of course. As previously stated, the scan codes should provide you the relevant information you need.
